I honestly believe GT7 is down 70% or more in daily players from launch, hence why we aren't even seeing bug-fixes... A lot of people bought it, and most of them aren't playing it. My PSN friend group has one person out of 14-15 that has been in the game in the last week; all of whom were playing daily in the first month but have since either gone back to Sport or other games. Small sample size, but I think it's pretty telling. It's the same experience I'm having, though I do still login to get my 2-5k cred roulette ticket.
Though even doing that 16min Tokyo grind 1x/day is getting harder and harder as the only thing that was really keeping me playing was grabbing new cars out of the UCD and LCD when they popped up. Both are fully cycled and I've got everything + duplicates from UCD and from the LCD everything except the XJ13, 917k, Mondial, 250 GTO, and 300SL racer. But at this point I'd be absolutely stunned if there was any content for these cars within 18mo, if ever, so I don't really even care if I miss them. Bought all the other LCD cars and aside from the F1 and Gr.4-Gr.2 cars they got an initial test drive and haven't been touched since.
Not saying I think the game WILL die; if PD is smart they've been keeping their mouths shut as they work on adding a massive single update that has enough content to tide people over for weeks or months (doubtful...) That could turn the game around drastically, but 2-3 cars and a couple of races a month isn't bringing anyone back, so if that is their plan to "save" the game as a live service I don't think it's going to work.
Unfortunately GT7 sold extremely well (at least from what we know from physical sales, though it wasn't topping Elden Ring) so it achieved a primary objective, hence nothing will be learned; expect the same copy/paste, unfinished, drip-feed live-service in GT8. Though I do expect some changes to how they approach 8 if GT7 fails to retain daily players (really wish we had Steam Charts to see the truth...) The early adopters of GT7 will know to steer clear of GT8 for at least the first year, but by then there will be an entirely new group of rubes that will buy at launch. Until Kaz is gone &/or the franchise is out of Sony's grasp, the only GT3-GT5 style of gameplay we're going to get is by dusting-off the old PS2's and PS3's. GT7 could have been the best game in the series, but they didn't want it to be great, they wanted it to be a low-investment/high return (not licensing cars/irl series and MTX's, respectively) cash-cow that constantly gives milk fo years to come.