Probably because retro is cool. I got back into audio about 15 years ago and started buying records because they were super cheap at the time. Then it became hip and the prices shot up like crazy. Glad I got a collection going before the madness. I prefer CDs though. 8 track and cassettes are crap for fidelity in my opinion and the only folks I know that have any R2R gear are over 60.
One thing that does drive me nuts is when they refer to records as vinyls. They are vinyl records for Pete’s sake not vinyls; at least get the terminology right. I am technically a millennial by the way but do not want to be associated with hipsters in any way.