I phone-screened someone from a FAANG, and they knew very little about non-proprietary technologies that we used on a day-to-day. Any of the big-branded commercial apps, they weren't familiar with, and I can hire someone for a lot less with the required working knowledge AND know that they won't be resentful about it.
I think it's going to take a year for some of the young engineers to level-set their careers in some places.
I'm trying to remember how long it took after dot-com bubble busting, and back then I know a lot who went back for their MBAs, Law degrees, etc. during a softening market. And I know personally how long it took for me to recover to the same economic level.
Also, I get emails a few times a week from recruiters saying something like "Ex-Meta Employee/ex-Faang available for employment", leads....
I had an eye opening experience several years ago. My group was partnering with a group at Google. Their developers were sharp, as one would expect. But were very lacking in what would otherwise be considered table stakes, the reason always wound back to they had a proprietary Google equivalent of X, so thus they weren't familiar with X. The one that really hit it home was that we had to teach them how to use Google Cloud, because at least at the time, internally Google folks didn't use GCP but instead used their own internal versions of things.
Kafka for 99% of developers in the company should be "Can I use our internal library to read/write some topic".
Most of what people are talking about can be learned in days because they’re 90% the same as other products. Sometimes it's hours as someone else said because they're just generic databases or a pubsub system.
Or the design is wonky because the new platform isn't a 1:1 match to the proprietary solution.
Occasionally X is an open source implementation of a Google paper, published after Google decided its proprietary tech no longer provides a competitive advantage and/or has moved onto a better architecture internally.
There's an astounding number of Google publications that spawned Billion-dollar industries.
Day-to-day tools are things that really takes no time to learn on the job imo. They take more time to get up to speed from scratch but when dropped into an environment using them I expect experienced folks to get up to speed very quickly.
If they resent not having the awesome dev tools though, like you mention, that's another thing entirely.
People leave, sometimes suddenly and without warning. The high self-esteem way to deal with it is to do your best to provide an attractive working environment, accept that some people will leave, and try to learn from each departure. That way you have the option of profiting from the talented employee who totally could make more at a FAANG but happens to like your company because you provide good management, a worthwhile purpose, or the actual ability to write code rather than deal with company politics.
Heck, having someone sharp with a new perspective even for a year could significantly improve things for the better. If you get out of their way of course.
Which is logging into Glassdoor or levels.fyi and checking. Shit you can do that right now and get some rough ballparks.