You may not realize how many there are total because most of them are regional. Things like Spectrum or Charter or Verizon or Cox or CenturyLink are all broadband carriers that were never available where I am, so I only heard about them through others online. Meanwhile, neither you nor this announcement mentioned my ISP.
As many of those are not part of this inquiry, presumably the FTC is not worried about the privacy practices of those ISPs at this time, and just targeting ones it has specific concerns about.
So sonic.net doesn't service your area? They were a great CLEC/ISP when I was in the bay area, mostly carried over AT&T lines so you could get it anywhere AT&T did DSL.
Thankfully, ATT just rolled fiber down my street last week, and I was on Sonic's preorder list the day after they announced it for my neighborhood. No timeframe, but I'm ecstatic to be using a local ISP again, not to mention symmetric gigabit with no caps for half of what comcast charges me.
When I lived in Chicago, the building I was in with almost 700 units the only choice for internet was AT&T DSL which struggled to get to 3 Mbps, simply because the wiring in the building was old.
I know a business in Chicago that has to do everything on tethered cell phone connections because the phone lines are too old to handle DSL, and the cable company won’t run a line across the street to their factory.
The only other two that have much more than a million customers are Altice and Frontier. I think you can argue that those 8 server nearly every American.
WTF?