Yeah, I tried on an Intel MBP years ago when it was first launched. It was super slow, and I disregarded it. I just gave it a try on an M4 Pro; it's not instantaneous like Vimmium, but it is usable. I am sold!
Oh, I don't want to play Pokémon games, but every few hours, I am given the controller and told to beat the boss with a team composed of 6 low-level Pikachus and zero healing items.
100% I used to have a 43-inch 4K "monitor" (16:9). The lack of curvature meant that at the sides of the screen, there was noticeable color shifting due to variations in viewing angle. That's with an IPS panel.
Your dream is probably a ~50in 8K TV (with RGB pattern if you are on macOS), but curved. I don't know if that will ever exist.
Personally, I found that with a bigger 16:9, I would not use the top and bottom of the screen. When I "downgraded" to a 40in ultra-wide, there was not much difference in the space I was using.
I have a 40in 5k (32in 4k, but wider). IMHO, 138ppi is the bare minimum, but it really depends on a person's eyesight and preferences.
I would love a large-ish ultra-wide with > 160ppi. One day, maybe, that being said, by that time those things will exist and be reasonably priced, my eyes might not be able to appreciate the difference.
My son loves Lego Mario and the app. He'll even go through the building instructions of kits he doesn't have just to see how they are built. The instructions in the app are super clear, animated, and the model can be rotated at any step to check whether the real-life model is correctly built.
Going back to paper instructions after using the app is a pain.