[johannes1234321]

> My entirely uninformed opinion is that if its possible to do everything TCP does over UDP we should do so just based on the fact that it is a simpler protocol

Everything which can be done with a truck can be done with a horse wagon.

Yeah, that analogy doesn't fully work, but QUIC is no perove of UDP being the right tool, QUIC is an iteration of TCP. Looking at some shortcomings of TCP (in the view of it's creators) and trying to fix those. If it is successful the chapters in your book will be as long as those of TCP and probably even lots of the content will be similat. It will do some form of connection negotiation (even more complex than TCP as it enforces TLS, which in TCP is fully in the application layer) and flow control. Basing it on top of UDP instead of using IP directly is not due to UDP being best, but routers, firewalls and operating systems being able to handle it. A new IP packet type would need lots of work by everybody.