Online authentication of any sort, beyond an initial check when first installing, in a single player game is an automatic no-purchase for me these days.  Steam is borderline as DRM, but at least you still have the offline option.  For now.

Publishers can stop pretending it's to stop piracy, because nobody is buying it except naive shareholders.  They want to fully control users access to their product at all times, and I won't have any part of it.

Yes we all know how much of an incentive DRM is to inspire, motivate and even force otherwise law abiding citizens in that direction but sadly After the cracking cometh the locking! (know your forum rules)

Naturally regional laws vary, just be clear about it up front so the mod's know, but they can still lock a thread regardless.