Seems like that's just for protesters.

That would be like showing up for the battle of Kursk with an M18 battalion. Might go well at first, you might score some big flashy wins, but....ugh... things are gonna get worse as the day goes on and it's generally an ill advised strategy

Rico as written and enforced walks right up to the limit of constitutionality in a dozen ways. It's built for speed. It's never really been thrown into a knock down drag out legal action between titans on equal footing (i.e. a bigco legal team, potentially helped by other bigcos). It might survive nominally but it probably won't come out the other end in serviceable condition

I say go for it. Heads I win. Tails you get RICO reform.

Anything trying to protect consumer rights at the federal level risks getting shut down during a future Republican administration.

This can also be true if the manufacturer of the product requires that retailers not offer a price below a certain amount. This is called the minimum advertised price (MAP) and is common for big brands like Apple. Another way to get around the minimum advertised price is to bundle the product with some other product or service, such as is done with cell phone contracts.

Blame the manufacturer for this, not the reseller.

Is it effective, like, at all?

The documents can be subpoenaed for a new proceeding from the source.

No, Antitrust law was effectively neutered by the Chicago School and their agent Robert Bork.

https://www.theamericanconservative.com/robert-borks-america...

(BTW that source is right-wing and can hardly be said to be biased against Bork).