You’re only counting JEPs, which are only for more involved features. There are lots of changes to the JDK apis that are used by other runtimes. See, for instance: https://javaalmanac.io/jdk/27/apidiff/26/.

Admittedly, the terminology here is almost designed to be maximally confusing, and I’ve never read a good post that laid out how everything relates.

Fair, although even there I don't know if I'd call that "lots" at just 23 added or modified methods that aren't in preview