When you say a "Mac" display, what are you referring to? Apple sells exactly one display - the XDR - and its pricing is such that no one casually buys because their $300 external display isn't working correctly. I very much doubt that is their motivation; it's likely just a (possibly misguided) effort to keep the UI simpler.

It was more of a $1500 external display ;-)

I'm confused. If this isn't a joke I don't get, would you mind sharing some advice on how to get it for that price?

I have replied to

"buys because their $300 external display isn't working"

with the fact that our external display was $1500. I'm confused now :-)

I thought you meant that the Apple XDR Display could be had for 1500. My bad.

No, sorry for being not more clear.