While I appreciate the goal, I do have to fact check your fact checking. :)
1. The MacbBook Air 15 comes with two Thunderbolt 4 ports, so in theory it can work with an eGPU. The actual problem that none of the GPU makers offer ARM compatible drivers for their regularly shipping cards. That being said, the TB4 ports do allow for docks and most other peripherals.
2. Immersive is subjective and audio probably more subjective than most things. Basically everyone fibs on this one.
3. "But if it's not something Apple makes, no one needs it, so it's not a compromise." Seriously though, a better argument is that everything in the tech world is a compromise. What they mean is "if you're looking for a basic, solid laptop, especially if you use iPhones, iPads, Air Pods, Home Pods, Apple TV...etc, then this will be perfect and without compromise."
On the other hand, as Whoopi Goldberg recently discovered, if you want to play Diablo IV... there is also no compromise: it just doesn't run it. (And that's obviously Activision/Blizzard's fault, right? :) )