I first recorded from vinyl to cassette back in the 80's, then transferred everything from cassette to CD at least 15 years ago, probably started the project longer ago than that. Then most recently put all of those on computer and thumb drives. Everything I have now is stored and backed up digitally. Both of our vehicles have USB ports for playing straight off the thumb drive. Also have Sirius/XM in both vehicles.
Cassettes do wear out, and start sticking. I had it happen more than once. Even CD's get scratched pretty easily. Having multiple backups digitally is by far the best insurance that your hard to find pieces will always be there when you want them.