I do this, then I make a copy of the CV as MyName_CompanyName.pdf in my Documents directory so I can refer back to it if I get an interview.
I've never struggled to get an interview with this method and I'm pretty sure I'm one of the mediocre people on HN.
It's also not something that requires a bunch of mental energy, so you can do it in the late evening when your brain is tired from the full day anyway.
From your other comment at the low end you suggest a 50% application -> interview conversion and 40% interview -> offer, in other words 20% application -> offer. That's a 90% chance of an offer after 10 applications. Maybe tailoring your resume gives you a 1.5x greater conversion rate, 30% overall, and now you only have to submit 6 applications for the same 90% chance.
All this is with FAANG credentials and presumably some other advantageous stuff correlated to that: good socioeconomic background, good education, no serious health or legal issues. Now suppose you don't have FAANG or you do have some other problem and your base conversion rate is 10 times lower, 2% application -> offer, 110 applications to 90%. With tailoring, 75 applications.
If it takes you 15 minutes to tailor your resume for each application, then in the first case with 6 applications that's 1.5 hours, but in the second case with 75 applications, it's almost 19 hours.
The point is that this is a rich-get-richer scenario where the extra work takes less time and is less necessary for the advantaged candidate than it is for the disadvantaged candidate.
You might argue that someone who is unemployed has all the time in the world, so why not. To that I'd say you should ask yourself how you'd feel about tailoring your 75th resume to increase conversion from 2% to 3% or if you'd rather just treat each application as disposable and keep moving on.