If you remove parking requirements then the marketplace can discover the right amount of parking. Parking minimums keep the amount of parking artificially high.

That's kind of eliding the whole point of parking minimums (which I also hate, by the way). Parking is a classic tragedy of the commons issue where each individual developer would prefer not to build any parking and externalize that cost onto nearby lots/public streets/following developers.

In fact developers did do this, and "the market" responded by creating regulations that prevent it. Which are obviously causing their own set of serious problems.