Bottleneck means that a certain component is a limiting factor (in this case during gameplay). There's different kind of bottlenecks (like for example hard drive speed and RAM can also be a bottlenecking factor) but in this example we will concentrate on the main things: GPU and CPU bottleneck. Also one important thing: You'll always be bottlenecked. There is almost no game that can utilize 100% of your CPU and 100% of your GPU at the same time. One component always will be the limiting factor.

Let's start with GPU bottleneck. This is the ideal thing - you want to be GPU bottlenecked. This means that a game will utilize your GPU to 100% and use all of its power. Your CPU not being at 100% means that it leaves headroom for other processes to run in the background and so on. Also a GPU bottleneck always will feel 'right' (so long as your FPS is high enough) and performance will be smooth. There should be no sudden FPS changes (maybe only for situations like huge explosions and stuff like that).
Things that will increase GPU usage to get into a GPU limit:
Higher resolution
Certain graphic settings (Like textures, Shadows, Anti Aliasing, etc)

Now CPU bottleneck. This means that your CPU is running at its limit (or if it's a game-based CPU bottleneck it means the game utilizes everything of your CPU it can. This can mean that your CPU is not running at 100% but at the same time GPU usage is below 95~% as well). CPu bottleneck is very ugly because usually your game will feel pretty clunky and just not smooth.
Things that can cause a CPU bottleneck:
Weak CPU (obviously)
Low resolutions
DLSS (some people think DLSS just lowers the game's quality and therefore gives you more FPS. While this is not wrong DLSS effectively lowers the ingame resolution and therefore decreases GPU load to achieve a better performance. When you're CPU limited it can even make your performance worse).
Crowd density and other stuff like that (because things like crowds are being processed by the CPU)

While of course the original release for this game was on PS4 and this is "just a remaster", there have been some heavy change in terms of details. If you really want to "enjoy PS4 settings" then set the game to 1080p, medium and 30 FPS. If your PC can run that and still has a lot of headroom in terms of GPU and/or CPU usage then congrats: Your PC is capable of running this game way above PS4 settings.

PS5 as you may know has a Performance mode and a Fidelity mode. Performance mode uses a mix of Medium-High settings and aims for a higher framerate. Fidelity mode uses high settings with Raytracing and a 30 FPS cap. On PC you can go even higher with a lot of additional settings you can set to Very High and even freedom in terms of resolutions.
Try to crank up your resolution and graphic settings while reducing things like Crowd Density and at the same time turn off DLSS; etc to see how far your GPU can really push. Then, going from that, you see how powerful your PC is in comparison to those consoles.

Marvel's Spider-Man Remastered is a great port but it is quite CPU hungry. You can especially feel that when you're swinging through the air and then suddenly dive low near the streets. Your FPS may quickly lower by a huge amount because now the CPU has so much to calculate.
Most people who complain about this game's performance are most likely in a CPU limit. I often read statements like "DLSS in this game is broken because it makes it run worse or has no effect" and "it doesn't matter which settings I use the game always performs the same". This precisely is an indicator for CPU bottleneck.
Also leave Raytracing off for now if you don't have a high end GPU. This can also be quite CPU heavy, especially with all the window reflections in Spider-Man.

Well, the most important thing: Try a higher resolution. I have a 1080p monitor and on my hardware (Nvidia GeForce RTX 2070 Super and AMD Ryzen 5 3600) in 1080p I'm very often in a clear CPU limit. In 1440p this is a whole other story: The game looks and even performs better. The highest framerate might be less now but the game is running much more stable so it feels smoother.
I still get into a CPU limit sometimes but it's way less in 1440p.

In case of 4K I do this by using a featured in the Nvidia driver called Dynamic Super Resolution or DSR for short. This can be used with any modern GPU (in AMD terms it's called Virtual Super Resolution aka VSR). DSR basically renders your image multiple times and then merges it into one image. In some games there is something similar called Supersampling.
The only disadvantage about DSR is that only 4x DSR looks great. All other settings look washed out or pixelated. So 4x DSR of 1080p would be 2160p aka 4K.

Fortunately Nvidia came out with a different version of DSR called DLDSR (Deep Learning Dynamic Super Resolution).
Here you can select 1.78x and 2.25x, helping you achieve 1440p and 1620p on a 1080p monitor. Compared to DSR, using DLDSR first DSR is applied and then an AI tries to make the image smoother. Doing that even these resolutions look great.
The disadvantage about it is this only works with RTX GPUs.

Other things you can do to make your game feel smother are:

Try using Gsync/Freesync (This technology adjusts your monitor's refresh rate to your FPS to make games feel smoother. While Freesync is software based and works with AMD GPUs, Gsync is hardware based and only works with certain monitor's on Nvidia cards. For some time there are Gsync Compatible monitors tho (so basically Freesync Monitor's that also work using Gsync). Gsync compatible monitors don't work as well as Gsync monitors but you can then use Freesync with Nvidia cards as well. And trust me: It does wonders.)

Cap your framerate. A reason why Freesync/Gsync works so well is because your Hertz and framerate are being synchronized. And on the contrary a reason why CPU bottleneck feels so bad is because your framerate will constantly be all over the place. If you cap your framerate to a fixed 60 FPS they're constant and therefore will feel smother. Thankfully Spider-Man has an option to aim for a specific framerate and if you get under that framerate the game will lower certain settings to achieve your desired framerate again. Works really well.

Overall I'd recommend trying out Digital Foundry's optimized settings.
https://www.youtube.com/watch?v=xI2VUQsPqJo
Combined with 1440p the game looks great and runs with 70-100 FPS on my PC (however in the meantime I switched to a locked 60 FPS using the ingame limiter + Dynamic Resolution Scaling to achieve a stable framerate)
Also make sure you keep something like Rivatuner Statistics running (or GeForce Experience) to check GPU and CPU usage, so you always know what the current limiting factor is.

I'm not saying that the game's optimization is perfect (there can always be some more performance patches) but I hope this made some people understand how performance in games is working. If you have things to add or suggestions, just leave them in the comments.