unless they're personally bought off.

You've said exactly why it won't become a problem for 'big' tech.

And there won't have been time for them to be bought off by ALL those groups right at the bill's passing.

Give it a week and those with deeper pockets will do so. Smaller ones... well, it's business, if bribing officials does not bring you enough influence/$$$ to justify the bribe, shutting off Canada is also a choice for a smaller service/business. Now, IANAL but i doubt Canada can use it's own draconian laws to prosecute a foreign entity in any meaningful manner (cue Google being fined in Russia for a sum big enough to bankrupt literally anyone).