Well that applies to any protocol , ISPs don’t block anything , your company usually do though .

UDP is very commonly blocked in almost every corporate environment I have seen, it is a pain get it enabled for applications like video streaming which benefits from UDP

Well, then you don't have internet access in your company. Only some fossilized subset of internet. They have intentionally excluded themselves from any kind of progress, so arguing against any new kind of standard because some people deliberately exclude themselves from new standards is a non-argument in my opinion.

It's like arguing against a developing new TLS version because people configure their firewalls to block any flavor of TLS they don't know.

Expect it is not just configuration. It is hardware too. I am member in a internet provider by students. We couldn't allow an UDP since we have an agreement with our uplink that we will make it impossible to host outwards facing services. To guarantee that for UDP we would need a stateful firewall, which we didn't have. Due to agreements without uplink they want to have full access to our firewall and since they only use Cisco, we are required to do so too. This means we had to shell out €€€€€ to get a firewall from Cisco and we had to put aside money to do that for years. Then our (old) core router had 90%+ load during testing of the firewall since the hardware UDP support it supposedly had was not up for the task. So we had to buy a second core router where we lucky weren't bound to Cisco due to outside obligations another €€€€ investment. It's not just stupid configuration, sometimes it is just means and it takes long strategic planning we can do as a non-profit to afford such things.

> We couldn't allow an UDP since we have an agreement with our uplink that we will make it impossible to host outwards facing services.

Again, that agreement already means you're not providing internet service, even if you provided outgoing UDP you still would be violating the end to end principle. The hardware is just a consequence of wanting to be more (rather: less) than a dumb pipe.

So what are we then? I think we are better internet provider than any commercial one could be in the dorms we supply. Being an internet provider is being more than a dumb pipe. There are regulations too. We have to do customer service, keep up times, ... But according to you we are not an internet service provider.

Even today I am forced to deploy TCP fallback pretty much everywhere, even with corporations "whitelist" us, mainly because they have many/many PoPs all over the world. There is no guarantee their system-wide policies is actually applied at a particular access point/ device for any number of reasons.

It is particularly worse in consulting industry, This is usually because their customer actually controls the network/infra for the teams working with them, usually that means a lot of fragmented IT managment.

This is from my experience deploying Flash / WebRTC stack video tools in Fortune 500/2000 type orgs in last 8-9 years. One of the main reasons we moved to WebRTC from Flash early on is because the heavy friction for deploying RTMP/RTMPS(E). I can count in one hand how many of them had sensible network polices.

You may had a good experience with network policies, many many large organizations still insist on IE11 and restricted networks world around, that is the sad reality .

There is a whole generation that have grown up woth ubiquitous “internet” access, but no concept that anything other than http(s) exists.

Do you know of any non-TCP, non-UDP, non-ICMP, etc services I can try out?

IPsec?

4G LTE is a godsend when companies or schools block stuff.