I wouldn't hold my breath. I'm not a Windows user, but my understanding is that the legacy code allows people to run old software, so I wouldn't expect this to go away just because the required minimum CPU is fairly new.

If anything, it should stay in place, as an argument to push adoption of Windows 11: "yeah, you need brand-new computers, but don't worry, all your old software will still work as before".

> but my understanding is that the legacy code allows people to run old software

There might be hardware support that can be cut, if specific x64 features are guaranteed to exist on the newer generation or bugs are known to be fixed you can drop the fallback code without breaking anything.