As a counterpoint to your post, I was recently hired by a 3000 person company who paid an external recruiter to post a job on LinkedIn and do the initial screening of me, which was extremely light.
8 rounds of interviewing with the company virtually later, I was hired. The interviews involved a mix of live coding, system design, and general questions about commonly used programming languages and frameworks.
I personally feel like the recruitment firm was beneficial to the process in getting my foot in the door and accelerating everything. I've seen many people have much worse experiences, but mostly from companies that aren't serious about hiring.
I’ve worked with good recruiters. They do a ton of work at the beginning of the hiring funnel.
If you got an onsite interview, you probably didn’t even notice the first few filters that the recruiter applied to you. Those early filters eliminate at least 90% of applicants.
Testing platforms charge the company tens of dollars per test, so it makes a lot of sense to have a person double check that the resume is relevant rather than sending tests automatically.
