Over here there are "consumer associations" that have the right to sue in such cases in the name of all consumers. That works quite well.

Due to this traditionally those things are not even tried.

That has changed with (mostly US) businesses entering the EU. A good example is booking.com, who again and again and again invented new dark patterns to then get sued for it, making it clear those are illegal.

We had the same with the airline industry with their advertised prices not matching the actual final price with all taxes and made-up fees. But by now even Ryanair has given up and no longer tries those tactics.

But there are no big financial penalties for losing such cases in court. I guess it's the bad PR these court cases generate every time that makes those businesses after a while giving up trying to screw over consumers...