Yes, and that makes not that much of a difference because you find almost no time to properly grade their assignments.

I disagree. We teachers have plenty of time to properly assess student work. But we also have to give accurate, consistent and fair grades and usually written feedback as well, and that's what usually takes forever.

An hour a day with 30 kids is enough time to meaningfully interact with each student if you're not wasting the whole class period lecturing.

What do you mean by "meaningfully interact"?

Non-meaningful interaction might be saying hello, asking if the student is present, asking the student "Where is the homework assignment you were supposed to turn in?"

Meaningful interaction is checking in with the student regarding their understanding of the course material. Providing clarification if the kid is confused on some point. Allowing opportunities for the student to ask questions. That sort of thing.