https://auth0.com/blog/critical-vulnerabilities-in-json-web-...
Implementations can be written securely, but it's too easy to make mistakes.
Yeah, there's worse stuff from the 90s around, but JOSE and ACME is newer than that - we could have done better!
Alas, it's not changing now.
I think ASN.1 has some warts, but I think a lot of the problems with DER are actually in creaky old tools. People seem way happier with Protobuf, for example: I think that's largely down to tooling.