"Are tech job interviews really such a nightmare?"
Yes. It's not just about the leetcode questions - the entire process of interviewing in tech these days is Kafkaesque. Interviews with half a dozen people or more, take-home assignments, radio silence for weeks... and then it's not uncommon for them to pull the req and have to start over with another company.
Last year I did a rush of interviews with a company, kept being told I was a top candidate, etc., "we should have a decision next week" every week for five weeks, another interview, a "we should have a decision next week" again, and then... the req got dropped. About six weeks later they opened up a different role that was also in my wheelhouse with a different manager, but... they wanted me to do a homework assignment that meant spinning up AWS resources to try out their thing and write about it, which required a demo signup (which went into /dev/null because they gave me the wrong link), etc. Finally I decided "eff this" and dropped out of the process.
"Jobs are also becoming better and lower risk"
I guess that depends on what you consider risk. I consider having to switch jobs frequently a risk in and of itself, because I have a family and need the insurance. When you switch insurance frequently, expect pain. "Oh, we're just going to deny your claim because we 'think' you have other insurance, we see here you used to be insured by..." (Not to mention starting from zero with deductibles.)
To sum up, yes. Absolute bloody nightmare.