Here's the thing. Your idea of "what I don't watch" and someone else's idea of "what I don't watch" are going to be vastly different. By eliminating bundling (the practice of forcing cable companies to carry secondary channels to get access to the primary ones) you'll force a race back to the bottom in terms of content. It will be like the old days of the OTA networks where you have to appeal to the most people to survive.

Things like Science and the Military channel almost certainly would not survive in an a la carte world. Without a subsidy the cost of programming will be too high and ratings too low to be fully supported by advertising.

This is kinda crazy; but I'm willing to suspend disbelief.

People who want to watch the station won't pay as much as the company can make from advertising to people (on that station) who primarily don't want to watch the station?

If I make shows on two channels, A and B. Then sell access to those channels forcing the carrier to take A+B when they only want A. Aren't I just charging more for A - which gets paid - but needlessly filling B with programming?

Is this just so cable companies can offer "100 stations" as a headline in their advertising?

The idea is that the subsidy takes B from losing money being profitable.

Truthfully, only the individual networks know whether the subsidy makes them additional profit or allows them to profitably air networks that they wouldn't otherwise be able to.