First, I actually believe white boarding questions (at least the automated kind) are assigned more indiscriminately than take home assignments. Many companies just send you online timed hackerrank or leetcode questions as a preliminary filter.
Second, the entire interview process rewards people who study for the interviews rather than those who like to build projects. Unfortunately I believe companies miss out on a lot of qualified candidates, albeit reducing their false-positives from obscure algorithm-type problems. With so many applicants, reducing false-positives ensures quality hires so it works on the company’s end.
Overall, my opinion is the interview process is relatively broken. Take-home assignments offer more insight into actual development skill, while whiteboard questions filter out a large portion of people (many who would be just as good, if not better, at actual implementations.) But it works for the interviewers so change seems unlikely. This is just my experience for new graduate interviews; perhaps it is different at higher levels.