Tagging everything as a "utility" and demanding they be regulated as such is as far removed from the conservative ethos as the altright apparently.
Where do we draw the line between a company "abusing" its network effects and a company avoiding being abused by other companies? (e.g. Imagine a app store that distributes only free software backed by a big corp, then a small proprietary app maker complains that they don't want to accept their app because its proprietary).
Is the size of the company the criteria that decides if they are in the right or in the wrong?
I don't think the app description of Gab is an appropriate content. Google seems to assume that the content of the Gab app will be innapropriate. Given this is about freedom of speech I'm not sure they should be the one deciding this. Are they also removing Gab from their Google Search results?
Yes. That's the whole point of antitrust law.
They ran atop the same network that everyone else had access to and achieved, the accurate analog to the railway example is the ISPs and not these companies.
Were Google just one of many available app stores for Android, would this be a weaker case? (Or: would railways have been regulated as common carriers were there several parallel railways next to each other, or if the track owner was not the only person operating trains on the line?)
What if OS + Store integration was done at the cell phone manufacturer level? What if they all ended up settling on the same default store (say, Google's?)? Would it depend on why they had selected that one? Would it depend on how many others existed? (And same question if OS + Store integration was done at cell network operator/phone reseller level.)
What if there was a plethora of app stores that various phones came with, but they all or almost all independently decided an app was not representative of them, or distasteful, or inappropriate?
Yes. See US vs. Microsoft.
What if Microsoft had never made a browser, but 90% of manufacturers chose to make Netscape default over Opera, and Opera sued them for it?
Also, why only comment on one of the scenarios?
Railroad law and regulation from a century ago is worth studying when trying to figure out how to deal with monopolies with strong network effects. Railroads had even stronger networking effects.
[1] https://books.google.com/books?id=sU0sAQAAMAAJ&pg=PA202&lpg=...