Variations of this have discussed during the constructor property promotion RFC, and more recently in the records RFC.¹ As with previous changes, this needs a discussion on the internals mailing list. My expectation is that you'll likely face significant resistance to this change.

@iluuu1994 thanks for the answer. Records RFC pushed me to implement such feature for classes as well, making "records" look similar to classes to prove that it could be done "with classes"
Btw, it's just a part of process of simplification creating classes

classUUID(privatereadonly string$value);

This is what you need to create a data transfer object

Btw, I'd like to discuss implementation. Theoretically, will it be enough to push the RFC further?
Now the "short constructor" is just a sugarred version of long constructor. Tests with AST printer prove it.

Btw, I'd like to discuss implementation.

Generally, I don't spend too much time on implementation before knowing that the RFC actually progresses. Most RFCs die before they make it to the vote.

Theoretically, will it be enough to push the RFC further?

Yes, RFCs are the only way to land language changes.