Yes I do think it has merit. I think some kind of specialized IQ test which measures for aptitude can be used for for screening. Of course it's not a be all and end all but it should significantly reduce the 'grinding-leetcode' situation.

Why not do that for all jobs. Forget resumes and work experience/accomplishments, and just hire based on a test score?

Perhaps we could administer this IQ test at age 12, so that the low-scoring individuals can go straight into the fast-food industry, and the rest can pick between the doctor/lawyer/SWE offers that will be showered upon them?

He said standardized test, not standard general cognitive test.

The tests that carry the particular branding "IQ" (Wechsler / Raven's / etc.) suffer from some problems in this regard - not very many questions exist and there are very large coaching effects. (Also, psychologists will tell you that getting an accurate result means you need the test to be administered by a trained psychologist. This is mostly nonsense, but to the extent you believe them, it's cost-prohibitive.)

Hiring from a test that measures IQ is a very good idea (and there is a test that's commonly used for hiring purposes, the Wonderlic†); hiring from "an IQ test" is a bit less good. Anyone who wants to subvert the Raven's test will be able to do that. High-stakes tests need more security.

The concept of "IQ" can be toxic in contemporary American politics, so there are many more tests that "happen" to test IQ than there are tests that advertise themselves as testing IQ.

† https://psycnet.apa.org/record/1982-00123-001 : "correlations between Wonderlic IQs and WAIS Full Scale IQs were [0.93] for the main group and [0.91] for the cross-validation group". Note that this test involves only basic math and takes 12 minutes of the candidate's time.