The point I was trying to make earlier was that there is more than one way to enjoy GT. As a car enthusiast, the cars have always been the main draw to me and I have always felt very satisfied by that component of the games. If you are a racing enthusiast, I can see how you would be able to view the games as racing sims first, and car games second.
I don't believe anyone has said otherwise.
Please be aware that I am fundamentally stupid, but it does seem to me, as an outsider, as though Polyphony is taking the stance that anyone serious about competitive driving will be playing online against other people who are also serious about competitive driving. Hence their recent investments in Esports and Sport mode. The people who care mostly about cars will probably stick to the offline races in career mode against less challenging and more predictable AI so that we can continue to just rack up credits and buy/modify more cars to build our collections. Either way, however you want to play the game, you should be well catered to. I'm not seeing the issue with that.
The issue you're not seeing is that people who want to race off-line against the AI don't want automatically want " less challenging and more predictable AI", as can be shown not just by the comments about it, but that it's historically been discussed as a weak point of the series, and that every competitor doesn't need to offer AI that is " less challenging and more predictable".
As such those wanting to race off-line are not "well catered to" when it comes to AI.