Now try being not an ex-googler, or not so great on the spot. Have been a great Python developer for years but personally have given up on jobs that require “tech” interviews.
I do hiring for our agency, which consists entirely of non-rock-stars, at non-rock-star pay, solving non-rock-star problems, in non-rock-star time. We still do practical tests for all interviews. Some people, actually, do just get up and walk out. I wish they'd at least look.
We do problems on the level of "fizz-buzz" or similar. Quick 10-20 minute problems. We don't make full completion a binary success/failure metric. We just want to hear you discuss your thought process and see that you're aware of variables, if statements, and for loops. Because, yeah, turns out some candidates who claim years of programming experience ... aren't.
But no tricks. And we also make sure the request is suitable to the resume (think about it as resume validation). So we wouldn't say "Python person, write a method for us in C#" or vice-versa. Smart people can easily cross-train themselves once the job starts. It's more about finding someone who has the fundamentals and can apply them.
In conclusion, I would defend the hands-on "tech" interview as necessary and not even evil.
IMHO basic screens are needed.
I also want to see how a person handles discussing problems, I like writing out an API and discussing how to use it to solve real world problems, what are the holes in it, what are the implications of the choices the API author made?