I thought he was pretty clear. The internet itself shouldn't be limited to merely TCP et al. It's just wires.
It really doesn't care what sort of wire it comes to router and what sort of wire it leaves over. And then not really even what is inside, it supports up to 252 different protocols inside.
Now gathering and transferring information where to transfer is somewhat more tricky, but really IP is pair of addresses and some data.
What we're seeing today is that routing hardware is also parsing the session transport layer (and sometimes even more!). TLS 1.3 lies about its TLS version (pretends to be a TLS 1.2 client hello) because some big companies can't deal with arbitrary version numbers. To "fix" this problem in the future, the real version numbers in the TLS protocol are now pretty much randomized to ensure no new middleboxes look at them again.
Also take HTTP/2: most of the fixes HTTP/2 provides (basically forming a tunnel) are already embedded into smarter transport protocols like SCTP. Because of lack of middlebox support, using such an alternative transport wasn't even an option. Alternatives like SST also had no chance, leaving everything to the TCP-packets-within-TCP HTTP/2 approach because of compatibility.