Funcom have explained in the past why this happens when steam is experiencing issues:
Exiting Steam did not help, tried it 4-5 times. But restarting the PC allowed me to finally to log in.
you are lucky.
I did everything… impossible to play Conan. But possible to play others steam games
I’ve been trying for a good 45 minutes. I suggest that Funcom should consider making itself, like other games obviously, independent of the Steam subsystems mentioned above. At least it should be thought about.
The problem really has to do with Steam. I just couldn’t get into the game today.
Just close Steam and start it again.
Unfortunately, this is not a reliable advice. Joining works rather randomly and even if players made it over the first hurdle to the mod review, they were no longer connected when restarting the game, which is necessary for joining a modded server. Maybe it is more reliable for Single Player.
And it happens again. Second time for a week. 2 hours spend for stupid connection. Really sad, that i can’t refund game because it didn’t cost its money. Trash code, with stupid connection ideas. Why i need this frackin steam connection if i play on my own server only with my wife by local ip?
Since it is a steam issue, you can submit a ticket to them. Maybe this way, they will solve the issue quicker 
Shut Steam down and then launch the game while it’s off. This way both Steam and game will start after one another. Helped me at least.
When I was trying to start Steam first and then the game while it was on it didn’t work.
I tried this but instead of the usual “Unable to Login” message, I got “Steam online services are unresponsive”.
Steam doesn’t launch independently after I’ve launched Conan
I am also experiencing the same problem.
I had the same problem for 3 days straight after installing the game after a year since i’ve last played. I solved it by disabling all the “Virus & Threat Protection” and “Firewall & Network Protection” .Then starting the game for once. Quit the game.
Restored my Virus and Firewall settings back to Normal. Then starting the game again, i received a pop-up message saying Firewall has blocked the game. Click on the “Allow” option then you’re all set!
Hope this helps.
still happening
Ive just bought the game today 26/06/2023 and this is still happening?? Managed to get it working but then get stuck on the load screen with full load bar. Reinstalled and now im back to square one steam online services unresponsive. Ive still not actually played the game yet and ive dediacted hours to trying to get it work. What is going on??