What's the Next Epoch of Anti Trust?

A platform is a place, either physical or virtual, in which transactions have the cost of negotiating and delivering goods or services reduced. Platforms by their nature are unitary because they're really large. So platforms like uber does not sell taxi rides; it sells reductions and transactions cost. The question is, how do we define an industry that's always been thes of anti trust? When i was at the fedel trade commission, seven u a pepsy tried to buy seven up oare those in the same industry?