It will be used in ways not intended. The Sherman Act has been used by many politicians to go after their political advisories.
If the FTC wants to do this, then they need to go after the banks for their anticompetitive practices. How about Apple?
In the 90s, Janet Reno went after Bill Gates. It wasn't because of the browser in Windows. It was a result of Microsoft's reach into Congress, helping turn Congress over to the Republicans. Microsoft's execs didn't want the tax increases that were coming, so they went all in for Republicans. After the election, Reno directed the DOJ to prosecute M$. What a circus that was to see. Then, you know what really hit the fan, Microsoft backed Dave Stirling in California. Democrats were going to do anything they could to destroy M$.
Can you imagine someone going after Google, or Apple, because they won't let others put software on their devices? How anticompetitive is the Apple Store? Can I please remove Chrome off my Chromebook, and use Firefox? Google and Apple donate heavily to Democrats, as does Microsoft today. You're not going to see it used where it needs to be, related to technology, IMHO.
I'm not picking on Democrats, there are plenty of anticompetitive right leaning companies as well (The Banks, Oil & Gas Industry, Agriculture...).