How does prohibiting boycotts work with a free-market economy?

Asking for a frenemy.
https://mastodon.social/@arstechnica/114745234007330736

@paninid They can’t pretend to be free speech absolutists and laissez faire capitalists who are cutting red tape. Of course this administration never cares about hypocrisy or accuracy.

One potential impact is could force advertising on platforms that are clearly anti-Trump, pro-LGBTQ, pro migrant… :)

I also challenge how enforcible it is. All an agency has to say is the platform demographics don’t match the companys brand image and the business case doesn’t justify the expense.