The literal point if interviews it to judge. The point is to find people who will work in the environment you have. I have done work on codebases where bad code means people die, by indirect or direct results. This probably biases me. For example, I have coded in front of a group several times. This year in fact. Sometimes a problem involves multiple people thinking through it. That's probably why I don't care about panel interviews as well. I have had to explain myself in front of a group several times.

These are things that people find stressful, but they are part of my job and have been at nearly every one of the little over half a dozen jobs I have held. My current job isn't even doing anything important. No one dies if I make a mistake and I've still experienced explaining myself in front of a group and coding with several people onlooking. I just assumed that's how the job is as my friends in the same field have similar kinds of stories

People can be stressed I guess, but is normal and common events in your job are highly stressful, then I still say that's a sign that it's not the career path for you. For all we know, these jobs have these things because it's common on the job and a candidate should really feel at ease doing it. That's my opinion anyway. We can only form opinions based on experience and apparently, mine differs from yours.