Old stereo systems are also coming into vogue again as millennials are discovering the superior sound quality of vinyl over i-pods.
This is something I know about and have been in this hobby since they were new. There was a resurgence in vinyl for a couple of reasons. One, they produced those cheap USB turntables that could plug into your PC/laptop. That give millennials instant access to something from the past-cool factor. Two, the reissue 180 gram albums have given those of us with decent turntables, new ways to listen to our old music. Trendy movies even recent, often show turntables spinning music. You still see an occasional movie showing R2R's reeling, but nothing like TT's. Again, cool factor
On the other hand, most vintage stereo gear needs to be fully gone through and components replaced after all this time. This is expensive and if not, you're gonna get screwed. Plus....tape whether it be R2R or cassette is on the way out and has been dying a slow death for decades...if you go by the #'s. Biggest reason for that is the decks are the most complicated of vintage stereo gear and need someone trained in working on them. The tech schools haven't trained students in analog technology for decades. A lot of the old analog techs are dead or retired. This situation is only getting worse.....the more complicated the old deck, the harder it is to find techs. Right now there are about a half dozen techs in the whole country that can adequately work on Nakamichi decks, for example. Think of that...six people.
Yes, there are boutique studios still recording in analog and even many rock groups still make records available to their fans. And there is seemingly no limit to how much very well heeled (often very stupid about audio) customers will pay for present, top-end analog gear. But when you talk about the masses....analog already died a slow death. Niche marketing though being what it is, still gives us tape & records for now.
We have always been a nation about convenience...one format replacing another because it's 'easier' to use or because the Madison Ave boys told you it was better. But you can't bring a dead format back if there's next no one around to fix the units. Some things you can school yourself in and fool & poke around...not analog decks and generally not sophisticated receivers and separates.
Kevin