There was a guy in a senior tech role I once encountered in a consulting gig who never let an opportunity to put someone down publicly go by. One time, a young researcher came and gave a (remote) presentation. At the end of the presentation during the Q&A, this guy basically says, "don't you think that your project is a complete waste of time in light of factors x, y, z?"

For my project, I was building some tools that were helping me understand the problem space (which was new to me and that he fundamentally did not understand himself). In a team stand-up, which included the CTO, I shared that I had built a useful tool that was helping me and he chimes in: "I think that you just spend all of your time making tools and don't do any real work." Even if there was a conversation to be had about how I was spending my time, it was ridiculous that he was bringing this up for the first time not 1:1 but with the whole group. I resigned a few days after that interaction (which was probably at least the fourth or fifth time he'd pulled something similar in the two months I worked with them). BTW, he would never just say "you are a moron" but it was very clearly the subtext of almost all of the feedback he gave, except to the most junior people who didn't threaten him in any way.

I think your quotes around "insults" are a pretty good example of how you can use an otherwise normal question to cast doubt on someone without even changing the wording. That technique isn't limited to fairly benign examples like this, face-to-face communication has subtleties that are even harder to pinpoint, and especially if someone has social anxiety or trouble speaking in front of groups, something like that can materially damage someone without even having real criticism. If there's real criticism mixed in, especially if the person speaking has clout in that context, that person can either inform someone or totally harpoon them with the same exact criticism. That is a foundational skill among lawyers who take depositions or cross examine people during a trial.

abusive parents lead me to reading through this. truly can scar someone for life not having a good study environment as they develop, im still trying my best to be better at studying given the help of my s/o but some days it feels actually impossible to absorb and internalize things since its truly mental anguish I'm fighting through. it would certainly help if my s/o would be understanding instead of flat out disappointed in me for doing anything but study while he works (from home, in line of site from me, but i guess he doesnt see when i get paralyzed and completely lose track of time as im in my head beating myself up for not knowing what to do.. sorry.. this is a lot rn and im supposed to be studying as i type ;v; made an account tho just to reply here)