I actually apply for three similar AI/ML jobs, then I got three online coding challenges. It took me a lot of time to prepare and do the three challenges. But it turned out that the recruiter is extremely slow and bad performance on updating my status. And it took them almost five weeks to do the first HR phone screen for one of the jobs. I felt that they have no mutual respect for applications and totally waste my time doing their online coding assessment, and those assessments are not easy (leetcode medium to hard). If a company is not serious about recruiting someone, I felt that it is really a bad HR team they have.