I've done hundreds of interviews as the interviewer. I've had people seriously panic maybe once or twice in that entire time. I've heard occasionally that the rates for other interviewers were higher (but still low), if that's the case then they just sucked at interviewing.
Where did therapists come into it? I've never heard of anyone going to a therapist to pass coding interviews, that would be ridiculous. Learning to control your emotions is something people are meant to learn as children. It's a standard skill you're supposed to have to interact with others, like basic politeness. If you're having breakdowns as adults then it's expected that the situation is really intense, like the death of a loved one, breakdown in a relationship etc. Job interviewing is a normal part of life and shouldn't be as stressful as those things.
"It's already bizarre that candidates with many years of experience in the field have to study intensely for job interviews."
The whole "cramming leetcode" thing is way overblown, or possibly a modern feedback loop in which crammers are making it harder to detect genuine skill and experience. Again I've done a lot of interviews and nobody ever mentioned having to prepare for them. That idea seems to be a relatively recent idea (last ~10 years or so) and is probably a result of so many people competing for very highly paid jobs at a small number of firms. Normal software jobs should ask people to demonstrate their skills, but it shouldn't be something that requires exam-like prep for any working programmer.
