>Firstly it becomes very difficult to argue your streaming service has no 'commercially significant purpose' other than piracy when you're not making much money.
It is a bit of a concern, but I see it less of a concern than you.
First, we're talking criminal law here, so the state has to argue their case and prove your guilt, not you have to prove your innocence.
Second, you still get 17 U.S. Code § 512 liability protection (DMCA takedown notices and resulting safe harbor) and if you can demonstrate you followed this in court, it would be a lot harder for the state to argue you deliberate did something wrong, especially if this concerns "user generated content" (harder, not impossible).
Third, you're fucked already anyway, ask Kim Dotcom (from megaupload) about it. If the government wants to come after you, it will, regardless of this law, and even regardless of whether you set foot on US soil ever.
>Secondly it gives the copyright enforcing industry a big amount of leverage to pressure you into doing things as failure to cooperate could easily be argued to make your platform intended for piracy.
Again, the law sets out what you have to do to have liability safe harbor under 17 U.S. Code § 512. If you follow that, it would be hard for the music industry to argue otherwise, and it's also not their place to sue you under this law in the first place. It's criminal law, and therefore only the state can prosecute. However, the music industry certainly would try to nudge prosecutors into bringing charges under this law, and/or bring it up in an civil proceedings to bolster their case. It could backfire for them tho, if the state refuses prosecution, then you have an argument in civil court that what you're doing was not considered illegal and the state decided you are not an illegal streaming service (or at least, that there was no sufficient evidence to make that case).
So I think it's not a great law, especially not if you want to do a (user content) streaming startup, but it's not that bad either.