I could simply come and say the reason for the lack of true players' racquets on the market comes from the lack of true players on the courts, but that wouldn't be accurate, as the vast majority of professionals also play with bigass heads and thick beams.
Wilson's reasoning seems to be pretty straightforward, though, and even though it's already been explained in this thread multiple times by me and others, I can't blame anyone for not going that far back, so I'll repeat it. Basically, they had one of the greatest players of all time (THE greatest, according to the majority of fans) playing with a thin-beamed midsize racquet, and as a result fanboys would have tried to pick said racquet just for that reason, ignoring all its properties, pros and cons. They used to do so and expect god knows what amazing precision and touch, while in most cases having half-assed strokes and being used to light and powerful frames which actually prize a poor technique. Coming from that situation, you need quite a bit of time to adjust to a racquet like the Pro Staff 90 and use it at its full potential. The average person, though, wants immediate results rather than steady progress with a higher ceiling, so they dismiss the racquet as "too difficult to use", "too heavy", "too unforgiving" or "suited only to stark Serve & Volleyers and/or Flat Hitters" after a couple of hits and either come back to their old racquet or buy a tweener from another brand without even trying to find an halfaway (as the Six.One 95 16x18 could be, for example), resulting in Wilson coming across as a brand which specializes in heavy and difficult control-oriented racquets which only very advanced players can use effectively. Now, on the other hand, the great player I mentioned above has switched to
the Dark Side a bigger and more "mainstream" frame, so most hacks will think things like "Finally a Federer frame I can use too" or even "I thought the Pro Staff 90 could only be used by someone like Federer. Turns out not even he can do much with that", so Wilson is milking hard on that (totally s#!tt!ng on their own old products since they're there).
Sorry for the long reply, but ranting against Wilson's lack of a
real Players' frame on the market is always good to release some negative tension.
That said, would it be THAT unconvenient for Wilson to do something like keep producing the Pro Staff 90 and other classics which you just can't get from other brands in very small batches and without renewing as often as their other lines in order to save a little on production, advertisement etc? Maybe, but I don't see how (this has also been discussed, by the way). It doesn't seem to belong to their plans, though. They've leaked, here's a link to them:
https://imgur.com/a/iJix1
Since I managed to restock on my Pro Staff 90s, I lost all the interest I had in Angell (and other frames, for what it's worth, although that new Powerbridge Mid looks darn sexy), but if the Pro Staff gets dialed in, I'd be curious about a comparison with your other frames if you don't mind. By the way, which model is it? Since you called it "Pro Staff
Tour 90", it would sound like the very first one.