I have learned, for me, there is a mental chasm that gets crossed when I agree to start having conversations with recruiters. It's a crossing of the Rubicon so to speak, psychologically. It is me saying that there is a possibility that I will change jobs and by being open to that possibility, however low I think it is at the onset, I am mentally, emotionally, and psychologically moving away from being 100% committed and present to what I am currently doing.
That alone is taxing and that is to say nothing of being in active search and mid-stream in interviews (in my world interviewing is a full time job with loads of prep work and deliverables and presentations across anywhere from 4-8 different meetings with just as many different stakeholders) and the discipline needed to compartmentalize your current job and fighting against checking out.
Anyways, to your main point, I don't think it's algo based, I just think that this is the weirdest recession ever in that unemployment is mega low, lots of companies still need and want to hire, and while a lot are in hiring freezes, there are still lots of job reqs being opened daily.