The IRS is in no way cracking down on the exchanges. Now they are going to do their job and go after tax cheats who want to stick their neighbors with the bill. That is what the IRS does. Pay your taxes and ignore the IRS. Or cheat on your taxes and pay the price. Plus interest and penalties, and jail time.
The clear message with this is this: DO NOT MESS UP WITH IRS or else you can experience what it means to be in hell while still here on Earth! Now going back to the main story. IRS demanded from Coinbase to hand to them all their customer data (if am not mistaken) but Coinbase insisted that it should be limited to those members who are US citizens as they also have many clients abroad. I think later on IRS retreated their position and would just accept those from the US citizens. Fortunately for Coinbase, there are politicians expressing an alarm about the request and so it became a pressure for IRS to reconsider their demand and position.