All of those are still niche products/movements.
And currently there are no cars with Wankel engines in production.![]()
Actually rotaries are quite popular in drones and other applications that need high power in a compact package.
Tube amps are probably more nichey than vinyl records these days. Hell live bands in local bars are becoming niche.
Playing bass is definitely more niche than when I started out; used to be a kid on every other block with a bass and a small amp, not so much anymore.
I already cited analog open reel tape; hell I need to move my MS-16 as it is now worth about twice what I paid for it back in 2000 (used). But I plan on keeping my half track
Analogeezer