WordPress 5 only supports jQuery 1 while the rest of web development world have moved to jQuery 3 long time ago. One most trivial use case is spicing up your front-end with Bootstrap 4. This may be made to work but it can break with any random plugin or WordPress update.
Given that Classic Press is already a break away from WordPress legacy, it must be feasible to have it run with jQuery 3 for users who are happy to use a limited subset of compatible plugins.
What would be your thinking on this?