While the patreon TOS changes was his official reason for quitting the game, it is likely not the real cause. DS didn't like what BB was becomming, as he let his patrons decide the direction of the game via polls and such. DS sounded like he had big plans for Eric, but was pretty much forced to drop the character completely, due to backlash from his fanbase. He dropped a lot of hints in the weeks/months up to the patreon TOS changes, that he was less than happy with how the game was shaping out.
DS was one of the only people who dropped his game because of the TOS changes. Everyone else found ways around the issue, either by switching platforms (like the dev of dating my daughter) or by changing mothers/sisters into landladys/roommates, and needing patches to put incest back into the game. DS could have worked out a solution to the problem. It is likely that he saw an emergency exit and made a dash for it, because he didn't really care for the game as he once did.
Of course there is a lot of speculation and guesswork here, but it is a widely accepted reality amongst a lot of his players. Well, at least it was at the time. Maybe it has changed since then, I dunno.