Likewise, I've been having the same issue. Just had it tonight, in fact.
First it was while struggling with graphical issues that choked my PC's overall performance, so I bailed out, lowered the settings to something more manageable and smooth, and got a 12-hour ban when I resolved that, and also shoved into low-priority.
Then it was after a severe freeze on my end that came without warning, and locked up on me. My controls were technically still useable, though impaired (I could hit escape, but there was no menu, no feedback of mousing over buttons, there was no sound of things around me, just a frozen shot of Rem running forward. Closing and reconnecting just got me stuck at a frozen loading screen again the moment I reconnected, with the feedback of Paige dying in the distance, to the game assumed I just reconnected even though I was incapable of actual play), and waiting for that match to finish without me so I could ACTUALLY play normally again, resulted in a 24-hour ban because I was absolutely unable to respond to game visual while connected. Which again, placed me in low-prio (with a higher win-demand).
Now, I just plain failed to load into the co-op bots game "in time" because I hadn't loaded up the city prior to joining a queue for a bots match, and now I'm banned for five entire days????? Because I failed to load in for the first time??? (Edit: My low-prio demand has been UPGRADED to demanding six wins to escape low-priority, for failing to load into a BOTS GAME.)
That just punishes low-end setups for no good reason. My only takeaway from this is to just, boot up "Explore NYC" prior to queueing so that the game has the damn map already loaded once and ready to go with all the props and creep camps, for the next time I get into an actual match after I get unbanned.
Except the problem is, I shouldn't have been banned in the first place because of the technical limitations of my system, which aren't easily resolved in this current tech-economy climate. The fix to avoiding being banned for "taking a little too long to load in the first time" shouldn't be "just get a better system lol".
Steam ID: heroponazrion