I checked up on the Bike Karen story a few months ago. She's lawyered up, so there's a lawsuit against the media outlets in the works. Both sides have laid out the receipts for the bike they fought over, which more or less confirms the guy was docking the bike to avoid tolls. (He's low income and if he keeps the bike longer than 45 minutes, he gets dinged, so he's doing what's incentivized.) He squatted on the bike while it was docked to keep it available for his personal use without paying for it. The 'Karen' just used the app and got assigned 'his' bike, so he got in her face and forced the bike back. It was probably standard behavior for him, save for the virality of the video.

Here's an article from the summer with the (then) recent developments. I've tried finding the suit itself, but websearch is garbage and pulls up the viral event much more than the lawsuit.