I don't know whose young kids you're testing on (and they're all different so you're right for some of them!) but all the ones I've met are glued to a screen at every opportunity. They love video calls and talking on the phone and interacting with people via screen.

It will work fine for all the INTPs and similar personality types. The rest is screwed.

My preschooler is probably something like INTP. Teleconference learning is not working great for her so far.

It's easy enough to test whether someone is an INTP with an online personality test. Basically INTPs will look like autists. They don't talk unless asked and dislike the company of other people.