Back to the point here, I agree 100%. At some point, you reach your genetic potential and / or your potential given your training restraints.
But that doesn’t mean you can’t get “faster” or improve your performance. IMO, FTP should be used to help set your zones and not be used as an indication of “fitness”.
Heck, I’ll regularly just manually update mine because I know I am capable of handling higher workout loads. I couldn’t care less if that is my actual “FTP”, whether determined by AI or a performance test.
At the end of the day, the only metric I care about is how I perform IRL.