RSS. It’s still around but slowly dying out. I feel like it only gets added to new websites because the programmers like it.

honestly: activity pub, matrix, xmpp, markdown and soo many more probably. All of these would be able to solve our walled gardens problem, but the apps with a basically monopoly don’t have much of an incentivw to implement them

IPv6

I mean, why the hell is IPv4 still a thing??

definitely some alternative internet mesh routing standart, just imagine if every device with wifi or ethernet could just extend the network without relying on an isp, yeah they could still serve as a fast backbone, but they just wouldn’t be needed and no disaster could really ever disrupt the whole internet again

Markdown. Its only in tech-spaces that its preferred, but it should be used everywhere. You can even write full books and academic papers in markdown (maybe with only a few extensions like latex / mathjax).

Instead, in a lot of fields, people are passing around variants of microsoft word documents with weird formatting and no standardization around headings, quotes, and comments.