Corel bought out the company and totally changed the product ages ago, so I don't know anyone who uses the modern releases -- the pre-built userbase wouldn't accept the upgrades, and new artists are just going to Photoshop or Clip Studio.

But yeah, I'm gonna keep running pre-buyout PSP for as long as it still functions! (...alongside Photoshop and Clip, for the things they do better.) A little googling found a small-but-determined diaspora of people with the same plan.