I actually turned down a job, whose hiring manager was very excited (or desperate) to have me, after the recruiter sent me a link to a coding challenge. I felt devalued, that they didn't value my time, and I felt turned off realizing that this coding challenge was the only hurdle for engineers on that team. Note that I wasn't a fresh grad or anything, I had years of experience at this point from, what I assume was at the time, one of their big competitors.
Since the company can't make time for a potential "experienced candidate" (their words) during the hiring process, I wonder what else they can't make time for? Red flag for me.