Even if something lasts due to pure inertia it lasts. And something that lasts is pretty nice if you want a standard to last, or be implemented. The standard usually isn't the thing that you use to proof you can do something better, by being different. Because then everyone will have a harder time adapting it. People implement interfaces they dislike.

Since this is related to Webassembly, Browsers, the Web. The web has a lot of historically baggage, that one might have to work around at times, sometimes more sometimes less. There are good bits and not so good bits and in the end a lot of the time more modern web applications (whether you think they are good or bad) as well as web browsers jump through hoops to do things. For many applications there would be better protocols. But it became the dominant standard, a standard that is actually being used a lot and that is why it has become a success story. It wasn't a hundred times better than everything else. It simply was something that people managed to implement successfully and something where they were willing to deal with shortcomings, because there are great benefits in implementing the same standard as everyone else.

Don't know much about the US constitution, but it seems that it was largely good enough to make people work together that otherwise might have ended up fighting each other. That's what you'd get if everyone had a different idea about what a good constitution is. Maybe things are unclear, and maybe there are uproars because of things, but it doesn't even get to that if people don't agree on a standard or a constitution in first place.

And while over the years I often imagined how great it would be if everyone just used that better standard that has been there for a long time and nobody uses and is completely forgotten, if it ever had any popularity, then everything would be so much better and greater and I wouldn't have to do that senseless thing I am doing now. But if that standard doesn't allow for people to agree with it by implementing it it's essentially worthless (outside of maybe "prior art" consideration).

And like it or not we currently live in a world where designs persist due to pure inertia. But we know that obviously people are willing to implement these which means when a standard comes along that is similar to what already is there then having many people adapting it is realistic. Otherwise it's that super interesting university project that never makes it into anything in the real world.