Teacher prep for on-line classes is 2-3 times harder than in-person instruction. I am sure there are hundreds of examples I could cite, but COVID certainly proved that remote learning simply is not as effective for most students. There have even been many threads on this topic in this forum. All you need to do is search a little.
On a more personal note, early in my career as a teacher, I was selected by my school district to evaluate on-line learning as a form of remediation. The program was never adopted because technology-trained teachers like my teammates and I decided the instructions results were not worth the effort and expense. During COVID, my three grandchildren had on-line instruction for a significant period of time. Their grades suffered and I doubt they will ever catch up as they lost about a years' worth of quality instruction.
The most important thing regarding instruction is that what the unions say is most often opposed by the rank-and-file teachers in the classroom. COVID was an example. My teacher friends all wanted to go back to class, but the unions in collusion with the local school boards and state governments kept them out.