I have taken up a tangential small photo hobby that has similar fun but avoids the problem you mention- Instead of adapting old cameras to cheap sensors, I ada

I have taken up a tangential small photo hobby that has similar fun but avoids the problem you mention- Instead of adapting old cameras to cheap sensors, I adapt old lenses to modern digital backs. I've been using a resin printer to print adapter rings to go from various old lenses salvaged from a box of thrift store 1960's East German cameras to adapt their lenses (many times they were non-removable lenses too, so not always easy) to an EOS ring to be able to shoot with them with a modern sensor. Sometimes the results are wonderful. You get the old aberration, soft focus, bit of distortion when I don't get things aligned right.. it's fun and I'm not ruining anything of value really.