I think this is a good move overall. Remember, they're not phasing out tests entirely, it's over a 5 year period before they can develop alternative tests. I think US college exam systems are horribly flawed. For one, why are they run by a private non-profit rather than the government? They're also clearly not difficult enough, when at elite universities it's more a qualification than a determinant. In other nations,…
What are the odds that the UC system will make a harder test, and secondly, will actually get good applicants to take it?
A lot of people will take that test for sure. And if it turns out to be a good indicator, other states would probably accept the scores too.
Then California makes it free for CA residents and makes test prep part of the HS curriculum and you're on your way to solving a few systemic problems at once!