> specify some rules / annotations that would help its analyzer answer "Yes" to more pages
Isn't that exactly what AMP is? Whatever "rules" Google specifies will in fact, define a DSL/subset of HTML that can efficiently answer "yes". As people demand more and more capability in this ruleset, eventually you'll end up with something like AMP, only the syntax will be slightly different, but the fact that it is a weird subset of HTML will remain.
In a way yes, but isn't one of the "rules" that is has to be cached/re-served from Googles servers as well? That is a rather problematic one, especially wrt antitrust issues...
Isn't that exactly what AMP is? Whatever "rules" Google specifies will in fact, define a DSL/subset of HTML that can efficiently answer "yes". As people demand more and more capability in this ruleset, eventually you'll end up with something like AMP, only the syntax will be slightly different, but the fact that it is a weird subset of HTML will remain.