It seems reasonable to require a static list for privacy reasons. But not supporting pattern matching rules would seem to be an explicit attempt to stop ad blockers.
It's rich to cite privacy reasons for not allowing the blocking of ad sites whose goal is to spy on you.
Because if the extension knows what URLs you're accessing, and can send that data somewhere, that's a major privacy concern.
So this makes sense and seems good for privacy. But if it breaks uBlock Origin significantly, that seems like a very bad thing.
https://developer.chrome.com/docs/extensions/reference/decla...
I don't personally believe that solves anything. Domain names are cheap. If I don't want my ad to be blocked, I can just rotate through lots of them.
Google has responded to some pressure by upping the max number of rules and allowing some amount of dynamically defined rules.