Why no interest in reel to reel if you're looking for the ultimate sound?

If I could buy those $500 tapes for $100, I’d be all over this. Even though that’s way more than I’d pay for a record. I do own a B77 but no prerecorded tape so it’s not used much.

As daveyf points out, the OP answered his own inquiry in his first paragraph. Many astute responses by experienced listeners here. In theory R2R seems a good proposition. The reality is the tapes are too expensive and choice is limited considerably in comparison to buying records, CDs or streaming options that are available and very affordable. Many happy music lovers are doing just fine with these far more accessible alternatives. Mapman succinctly summed it up very well. 
Charles

I tried R2R twice in the last 10 years by purchasing the Otari 5050 and later the pioneer tt-901. My goal was to create playlists from my vinyl albums and from special events. The Otari was awesome but only at 15 ips. I tried a couple of prerecorded tapes at speeds of 3 3/4 and they sounded like crap. At 15ips, I was going they tape at a fast clip and new tapes were hard to come by plus cost quite a bit. I thought I would purchase a tape project Tape to play on the Otari and the cost and the lack of availability of artists I like, this didn’t pan out.I later tried the tt-901 and recorded everything at 7 1/2 speeds and didn’t like the sound and I still had the expense and tape acquisition issue. Gave it up forever now.

Selection limits it even before all else.

Size/space is another big thing for many.

Price may be an obstacle for many, but other equipment can get as costly so it is even.

Support for machines may not be perfect and how many of them are new under warranty?

Just setting the tape up to be played is getting less and less practical, as mapman pointed out, I think.

It does look nice, but how long does that novelty last?

Completely subjective, I heard one R2R setup at an audio show. I know, the room was bad, humidity wrong, and whatever else that could have been imperfect was imperfect. It might have been, to me, the most irritating sound of the show. I was hoping for magic and I got sandpaper. Under different circumstances, maybe it would have been bearable, though. To me.

technically you are right on.  better yet, get 1" master capability.
problem: software. end.
G