And I didn't say you should work for free. I said shooting back your hourly rate in response to a request for a tech test could easily be seen as unprofessional. If you don't want to do a tech test that's fine but you can just withdraw gracefully at the start of the process when you ask what their stages are and they tell you about the test.
I wasn't saying that I got paid consulting rates to do tech tests. I have never had to do a tech test, and never will. But I've been approached by recruiters, and I always respond with my current top-tier hourly consulting rate, with a minimum half-day charge. Usually that's the end of that conversation, but twice such an unsolicited inbound request has resulted in the recruiter saying "okay, when can you come out?" Once was a certain large asian phone manufacturer, who flew me out to their headquarters halfway around the world for a week of consulting, which also acted as a sort of interview. I decided not to pursue a longer-term job with them for $REASONS. The second instance was my current non-FAANG job. Told them my rate, they again flew me out for 3 days, and on the last day we negotiated salary.
To be clear, my negotiated salary from this job is much, much less than $5000/day I charged them for that interview. It's actually on the lower end for my industry, although I'm still one of the higher paid members on my team. I took it because I like the team, I like the work, and I'm given a fair amount of freedom. It was also 100% work-from-home, prior to COVID. The $15000 I invoiced for 3 days of consulting? They considered it a signing bonus.
But yeah, some companies are willing to pay to get the attention of senior talent, and since I'm charging hourly they respect my time. I have my pick of places to work, so why not filter based on that?
PS: my rate for 4 hours work is $2500. Companies HAVE taken me up on this rate. In fact I am currently declining work because I haven’t the time. Know your worth!