In my experience, using VTT for PbtA games is quite rare because, like, what would you need a VTT for? Any app that allows for a voicecall is more than enough.
Yup exactly. We played a couple of PtbA games online a fair bit in the pandemic, and in no case did we use any kind of VTT, because why would you? We just used which chat app was working best at the time (mostly Zoom because one of the players had a special licence for it). Whereas for 5E, we tried various methods, but the only one that worked well did involve a VTT (Roll20 with a browser extension linking it to Beyond).
Re: bad RPGs, I think there's a very strong correlation between RPGs which are aiming at a specific, merchandised IP, and bad RPGs.
And that's because, in most cases, either the system is just inherently low quality (i.e. just badly designed or rushed and incoherent) and relying on the IP to sell despite that, and/or the system is largely or even entirely inappropriate for the IP. I think an awful lot of these have been mentioned in this thread, and whilst I will avoid naming specific recent ones because they're definitely not the "worst ever", I'd say this still goes on, that we still see a lot of quite low-quality merchandised IP TT RPGs. Okay I'll name one - the new Marvel RPG. It's sad because Marvel, historically, has a long track record of pretty good RPGs based on it - FASERIP, MSHAG and Marvel Heroic were all excellent, but Multiverse? Oof.
The other big "bad RPGs" trap is similar/related which is where you have an extremely well-conceived (or at least interesting/fun/insane) world/setting that's original to that RPG, but the rules completely fail it. RIFTS being the best example here for my money. The setting is unique and bizarre, but the rules are generic crap which doesn't fit the setting. At least the Savage Worlds version kind of rescues it.
The final one is when you just have rules which are badly designed and hard to make work, even though they fit the setting, and this is kind of the saddest. The worst RPG I played significantly in the last decade is probably Shadowrun 5E, which fit into this category.