I think the main issue is that people would much rather spend their free time learning or building something useful, rather than the "prep game." A more skilled, knowledgeable workforce would benefit the corporate overlords as well, but we can't have that due to the broken interview system.
You change job every few years, spend majority of walking hours in job and your financials directly depends on job. Why would you not spend time on prep.
I have no sympathy for people posting "jobless for months and reject coding test interview" in one sentence.
