I think that I could see a couple of motives for ridding yourself of a technology you no longer believe in. One could simply be space - getting rid of your digital equipment saves rack space, and also storage for the discs themselves. If you lack space, that makes sense. Another might be money - but I doubt you would get a big return on your used discs and digital equipment. But maybe, as you say, enough to contribute to a good cartridge or something.
For me, I believe in diversifying most things in my life: friends, interests, equipment, beliefs (I do enjoy having just one spouse, however!) When I lock down my options to just one, or very few, I feel like I am missing the learning that the other options could bring me. I play vinyl maybe 80% of the time now, but spending time on Qobuz learning about new artists, or listening to good FM radio hosts talk about music, feels like a worthy use of my time. It is expansive, and I don't want to be contracting as I head into old(er) age.
David