WordPress 6.4.3 is meant to be a "security and bug fix" update, but in fact contains breaking changes to how it handles zip files (used by themes and plugins). Details here.
This breaking change should have been rolled into a minor version update (eg. 6.5) instead of a bug/security fix, and is a big middle-finger to the average WordPress user.
If you're getting the "Incompatible Archive" error when trying to install a theme or plugin zip file, you'll need to contact your host to update libzip.
Note: you can always find our latest supported WordPress, themes and Feast Plugin versions on the compatibility page.