https://gitweb.gentoo.org/proj/portage.git/tree/man/ebuild.5#n1119 doesn't mention the improvements in EAPI 8 for usev (bug 744868). Need to check while there if there's any other EAPI changes we need to reference on the page. (Noticed b/c of https://github.com/gentoo/gentoo/pull/33039#discussion_r1335239774) Similar to bug 914590