I have an old 7 speed touring bike that I wasn't using, but still held a lot of sentimental value for me. ...
If the issue is sentimental value or enjoying using something you have used in the past, that makes it a bit different. In that case, make the modifications.
Earlier this year I bought a used set of wheels that use clinchers to put on a vintage Italian racing bike that I had put is storage a couple decades ago after I got too frustrated with tubular tires. And, repainted the frame, new triple crank, new wider bars, modern brake levers & interrupter levers, threadless stem on quill to threadless adapter, etc. I still hate downtube friction shifters, but I like riding the bike. Frame and most components from 1961, the used wheels I put on it are from the 1980s, and as noted some parts are modern.
