We’re talking about replacing lost content here though. And as such you can use the streaming services as a “backup” by re-ripping your whole collection if you lose it.
I’m actually doing this now as part of a library cleanup. Zotify + beets are a great combo to pull down vast quantities of music and properly sort and tag it.
Then I stream it to my phone in my truck using ampache and ultrasonic, which does have a local buffering option.
However if you have some exotics that you ripped from rare discs, demos or prerelease, live recordings with sentimental value etc. I would suggest keeping those properly backed up. I don’t have many of these, but the ones I do have are backed up both cloud and offsite.
Personally I live in a very rural location and I farm, so I can spend a lot of time on the road or in my tractor. 1gb wouldn’t get me through a day in the field, so I have a pretty big collection with a lot of variety. We don’t even have reliable FM radio here, so it’s bring your own music or listen to the diesel roar.