That's cool, but you can't run standards. I tried Mono since its early days and kept trying until .NET Core came, but it was nowhere near production-ready, it wasn't enough for my school assignments, much less production.
I'm not saying it changes anything. Wasm is just a more modern attempt, like .NET itself. I don't see any reason to prefer one or the other only because of its age.
Well, I wanted to use Linux, not Windows. And my servers ran (and still run) Linux, not Windows. The point wasn't that I couldn't do my school assignments (I was forced to use Windows VM) but that not even this simple task could be accomplished - so running it in production was straight up impossible.
Wasm is much newer than Mono was at the time. Let's wait.
That is how Mono started.
Additionally here is some historical refreshing about two other attempts,
https://www.gnu.org/software/dotgnu
https://www.codeguru.com/dotnet/net-nuts-bolts-the-joy-of-ro...
A surviving clone of the repo is available here,
https://github.com/SSCLI/sscli_20021101
Finally, this doesn't change the fact that the CLR was only yet another version of this idea, there are plenty of others since UNCOL in 1958.