Which will also become a historical artifact as new protocols are made to use little endian.
TCP is becoming increasingly less relevant, although I don't know if it'll ever actually disappear.
Layers 3-4 (network, transport) are both big-endian - IP packet headers and TCP/UDP headers use big-endian format.
This means you can't have an IP stack (let alone TCP/UDP, Quic, Capn Proto) that's little-endian all the way through without breaking the internet.
Outside the webdev bubble, it's pretty much QUIC that is irrelevant - it's just another UDP based application protocol.
The OSI layer model is not necessarily as relevant as it used to be.
The OSI layer model is extremely relevant to the Cisco network engineers running the edges of the large FAANG companies, hyperscalers etc. that connect them to the internet.
I'm just pointing out that UDP is an extremely thin wrapper over IP and the preferred way of implementing new protocols. It seems likely we'll eventually replace at least some of our protocols and deprecate old ones and I was under the impression new ones tended to be little endian.
[1] https://www.rfc-editor.org/rfc/rfc9000.html#name-notational-...