Most Blu-ray’s now come with digital files. You can upload these to a server like Plex
Not really true. Those 'digital copies' are usually heavily DRM'd and even only available to play through a specified service (typically a streaming service). It's the same arrangement, where you're actually being offered "access" to a digital copy, but you don't own it (as you would a physical copy).
I know that ripping a DVD or BlueRay for personal use is officially fair-use under DMCA precedent, but I don't know that is the case for digitally distributed media, since each provider has Terms of Service that limit the legal uses. I don't know that it's been tested in court, but it's certainly not obvious if doing so is legal (and thus not a reasonable option) to most consumers, and so it's still not a true replacement.
Again, the legality of the practice isn't really in question here, it's that there is no reasonable informed choice -- if you're going by the letter of the ToS, there is literally no legal alternative to the digital 'lease' arrangement.
*Edit - I might also point out that the only thing keeping open the possibility of ripping dvd's and blue rays into digital files is the continued use and standard of BlueRay players. Other DRM types used on media files are much, MUCH harder to bypass (nearly impossible in some cases). There are some BlueRays that come with a physical DVD containing digital media files (.wav or similar) that must be played on a PC, and those are both heavily protected AND at a far lower resolution. As soon as it's no longer common to use blue ray or dvd players, distributors will absolutely lock it down even further. We are at a really precarious place as consumers, because the market has failed so badly at regulating itself (it's a meme at this point) that we're only like 5 years away from there being no legitimate alternative to digital media streaming, even to the dedicated and tech-proficient consumers.