I often see men used as a tool for the conflict/problem in yuri, so that may not be good there... let's hope for the best.
That’s not necessarily the case here—while Kuzoshiro’s Living With With My Brother’s Wife isn’t officially yuri, it’s certainly female centered, and in that series men are not just problems, sources of conflict, or completely in the background (as opposed to, say, the Kase-san series). Who knows exactly what sensei-san is up to right now, but just given the author and the tone here, I’d guess that the probabilities are against anything like sexual harassment or anything highly negative. But of course that all remains to be seen.
As to the way people treat people with hearing loss, the invisibility of the different ability really makes it hard to always remember it when you’re with them in a casual situation. People routinely turn their heads away or put their hands over their mouths when speaking, not to mention speaking very quickly, so if you don’t keep that person’s needs in mind all the time it’s easy to lose them. (My own hearing is OK, but in certain acoustic circumstances, like a large echoey space with lots of people and ambient noise, I can sometimes have trouble following conversations in a group.)
And how people with hearing loss have been coping with pandemic masking I can’t even imagine.