For example, in the Uber-or-Lyft 'battle', sure, there are and have always been private car companies and private drivers, but when you want a car you're likely to open one or maybe two apps on your phone and call the quickest/cheapest option. Similarly, Facebook competitors have a hard time getting off the ground because when you're the only one in your friend group on a new social network, there's no one to talk to.
Meanwhile, a new email provider has a small amount of work to do to catch up with all the security regulations, but then can just provide value to its customers without having to worry about 'defensibility'. A single app aggregating Uber, Lyft, taxi, and 3rd-party car services on one screen would open those up for competition. Similarly, a federated Facebook that provided various social networks in one client would let you pick your hosting provider, configure your own feed, and communicate with people on other platforms.
For now everyone is just waiting until Uber and Lyft run out of money, but longer term it’s really not looking good for them.
Is there any talk of requiring companies that have or intend to have effective monopolies due to network effects to make their services price-comparable (or aggregatable, in the case of the likes of Facebook where the "price" is your being served ads) in some way as you mentioned? It seems like it would do a lot to solve the problem. Not being able to shop around is antithetical to competition
I'm not sure this is a useful concept. Investors are burning billions of dollars trying to ensure that Uber-or-Lyft [or insert other unicorn battle here] gets un-catch-ably "ahead", meanwhile neither is a successful business in the traditional sense. There are tons of successful businesses in the world that just execute well and deliver value in exchange for money. They're not succeeding because they are "ahead" of the competition, they are succeeding because there is plenty of room for multiple competitors to succeed.