Worse, now device manufacturers can now make their devices identify as "apple" out of the box and advertise it as "compatibility with Apple AirPods features X, Y, X" and be legally permissible.

It's basically the consequence Google v. Oracle and the cases leading to it.

I think that's against the Bluetooth spec, and if you do that you won't be certified.

like every browser identifying as Mozilla in the user agent

What makes this illegal product tying under specific laws?

It’s, hilariously, the opposite: the exposure of this idea makes every other product better and Apple can’t change it (until they do).

Product tying is not a thing you can bypass.

This is idea is independent of whether Apple’s strategy is good or bad, legal or not. Product tying can’t be undermined, or it’s not actually a problem.

I still don't see the illegal part. I am in VFX and have three dongles connected to use specific software packages...

Dongle-based license management or DRM isn't the same as product tying; each dongle just validates the license for the use of a piece of software. But forcing customers to only use ink cartridges from a specific brand, deliberately rejecting or invalidating third-party refill options? That is a form of product tying, and it is being deemed illegal in more and more countries.

How is Apple forcing anything with AirPods and how is it illegal?