Installed from my backlog and tried to play it today, and without even talking about DLC maps, it just brings up a screen saying its checking for updates then says "a service is not available", and exits. Is this now completely dead?

I want to have access to the dlc gold edition maps, but the server is down and I can't, what should we do?

Steam will not let you review it to warn others away until you play it. You cannot play it because the packaged installation is broken. Steam knows this and continues to try to sell it to people. You can spend a few hours finding a way to finally get it

I played Settlers 7 online multiplayer a week or two ago and it worked. But today I'm not able to search for online games. Is there a current issue?

https://www.pcgamingwiki.com/wiki/The_Settlers_7#Access_Ubisoft_Connect_rewards_.26_all_DLC.2Fbonus_content Take a look here.