The "newest iPhone" analogy is completely flawed though. The right analogy, if you want to go with that, is you and your friend go into the Apple store. You both purchase the "iPhone 13 Pro Max", and pay the same price, but for some incomprehensible reason yours came with the A14 CPU and the 60Hz screen. You're arguing that this is perfectly fine, that anyone who disagrees is being ridiculous, the iPhone 12 internals "work just fine", there are "probably drawbacks to the updated parts anyway". All of those things would be valid arguments for not upgrading to begin with. None of those things are valid arguments for a company selling customers two versions of the same product, at the same time, and at the same price, where one has significantly improved internals.
And yes, one day down the line, when you sell your "iPhone 13 Pro Max" that, for some weird reason, came with the iPhone 12 CPU and screen it will be worth less. And there will be a day, when Apple draws the iOS support line at the A15 CPU, that you will not get updates despite having an "iPhone 13"
That is your iPhone analogy. It's not about "making people feel bad for what they got", it's about not defending a customer hostile move by Tesla. As for the difference, it was the most significant positive thing I noticed when checking out my friends refreshed S in comparison to my 2020. Definitely more significant even than the reasonably improved interior quality. The performance difference is immediately noticeable every time you touch the screen which, especially with v11, is constantly. It isn't just for "games and YouTube" (which I completely ignore). Every single aspect of the UI is dramatically snappier. Once you've used it, going back to the Atom based MCU2 feels like a significant step back. On its own it might not be enough to warrant an upgrade, but it's definitely more than significant enough to be pissed off if you paid the same price yet didn't get the updated part.