The T152754: Configure filters in a single extensible place refactoring technically doesn't break this, AFAICT. It doesn't inherit from ChangesListSpecialPage, so it's not affected by whatever we do there.
It has only a few conditions, which it handles its own way (e.g. namespace, hidecategorization).
It also fires SpecialWatchlistQuery, which was already deprecated before this refactoring, and only with an empty array (not with fields provided by the user).
So I don't think the refactoring worsens the situation here, but we should re-evaluate at some point.