A corporation could replace TCP with some proprietary protocol (but I don't see why would some even think about it) but can't replace IP: IP is the protocol tha

A corporation could replace TCP with some proprietary protocol (but I don't see why would some even think about it) but can't replace IP: IP is the protocol that routers on the internet use to know how to route packets, you can't replace it without implementing the new protocol on all the routers that your packets have to go through and those routers aren't own by a single company, so TCP/IP isn't going anywere soon and probably would never go away.