Well, Bleem went down under the weight of Sony's lawsuits, just like Yuzu did with Nintendo's. Sony didn't even win any of their lawsuites against Bleem in the end, but constant legal trouble is usually too much for small startups to handle. The US's legal system essentially allows any company to duel any other, with legal funds as the weapon of choice, and the bigger weapon wins every time. Legality doesn't matter unless both companies can truly afford to fight the battle to the end, and emulators will likely never have that power. So all we can do as consumers looking for options is to try not to talk about the little guys so much that one of the big guys feels it's necessary to bury them to death with lawsuits.

Money is not what makes it legal/illegal. But asking for money is definitely poking the hornet's nest.