Those are nice points; I quite agree there are things one can do to engage people over Zoom etc. But it's less spontaneous and takes more prior planning. Also

Those are nice points; I quite agree there are things one can do to engage people over Zoom etc. But it's less spontaneous and takes more prior planning. Also, many students simply do not want to ask a question in front of their peers, online or in person. When in person, there are other cues I can use to detect student confusion -- frowns, someone trying to decide if they should raise their hand, a barely audible "um..." -- but online all of that is gone.