> I fear I'd be blacklisted on some list these companies might share, should I bomb one without a lot of time spent reviewing.
AFAIK they only blacklist you for 6 months and then you can try again. Even that may be relaxed if you're trying for a different department or, especially, geographical location.
> numerous days of vacation time used for these interviews in California, it doesn't seem worth the effort.
In India at least, the big companies handle this better than smaller ones - they have one or two telephonic interviews to begin with and then finish off all the face-to-face interviews in a single day.
I sometimes follow a Reddit sub geared for mostly recent CS grads. Every week or two will be a post from someone who got a FAANG job, detailing what he did in order to pass the interview. And some of these are pretty absurd - graduating last semester and since then spending 6 months going through leetcode 6 hours a day, studying algorithms, paying for interview training classes, etc.
And as an older guy who has a decent CS degree but hasn't needed to use 90% of anything related to algorithms in 15 years, I'd have to study a lot, and along with the numerous days of vacation time used for these interviews in California, it doesn't seem worth the effort.