My problem with forums is that I am forced to use a web browser and access them through their provided interface. A lot of them, especially the older ones, are seriously hard to use and even worse on mobile.

Mailing lists I access with my preferred mail client and environment.

Receiving "10,000 emails per day" would only happen on a very active list. In most cases you're talking about a dozen or at worst a few hundred. Your email client can easily filter those into a virtual folder, and quickly find the messages where you are addressed or threads you're interested in.

Once I have the emails, I have them forever. I am not dependent on some forum remaining online five years from now if I want to go find an old message.

Web forums and wikis just suck for message-based interactions. Email is designed for that and it works really well.

I find that people who complain about email volume are not only unfamiliar with setting up rules to file messages into folders, but entirely uninterested in learning how to leverage their tools that way.

In fact, it seems many of them resent having to learn anything in order to be more productive, instead insisting the burden belongs on others. “I don’t want to get all that email, so it’s OK for me to make you visit a web page several times a day to participate instead.”

And no, Discourse’s “mailing list mode” isn’t sufficient, it’s as garbage as the rest of Discourse, especially when D showed the right way to do this: Mailing list primary, NNTP newsgroup gatewayed (or vice versa), with a web forum for those who insist on one.

If only LLVM et al had gone that route.