It seems like nobody is content to maintain a commercial product that does one thing: play media well. Plex Media Server is now going down the same path: They're trying to do their own streaming services, be a portal for podcasts, have a partnership with TIDAL, etc. They recently hijacked the home screen UI to shill their library of completely awful TV shows and movies that nobody wants to watch (though it can be disabled easily). Seriously considering a move to Emby at this point.
Well, at least in Plex's case I'd assume it's to generate a reoccurring revenue stream to continue development. I question how sustainable the "Plex Pass" feature is with so many people (at least that I know) who bought a lifetime subscription ages ago. I personally bought a Plex Pass for like $49.99 around 6 or 7 years ago and hasn't given them a cent since then. I support their efforts like Tidal and ad-based TV and Movies if it means I get new features without having to move to a monthly or yearly based subscription service.