I've never done an interview at a place like that where I've worked (even in my early career), but you're very, very likely correct if you want to get into a FAANG early in your career without being able to "shop" around. My experience isn't universal to be sure, but neither is the opposite. :)

Leetcode interviews are thing everywhere now. The days of getting an interview from medium/large firms because you have 20+ years of experience on your resume are over. A lot of companies use “online assessments” with timed leetcode problems that require presumably perfect scores to even get a human on the phone. They seem to range from comically easy (Amazon) to impossibly difficult (Microsoft). I highly suspect they are outsourcing this and the questions are chosen randomly, as the difficulty varies wildly for identical positions.

Maybe this is a recent pandemic thing, not sure. I started job searching this year and I’m totally blown away by leetcode-ification of hiring process.

There’s a few notable exceptions- Facebook and google will fast track based on resume, and some medium sized companies if you’re applying for a specialist position. Otherwise you’ll be spending nights and weekends drilling all the silly leetcode tricks into your skull.