Mailing lists (and newsgroups!) are really really really simple forums. Still used widely in the open source community. Lots of hosts out there, very low investment in cost/time/maintenance, the 'friction to post' is a feature not a bug, you don't need a weird client or server, the archives are publicly searchable, you can filter them at your leisure and use different lists for different topics.
If you want to gamify your community engagement, StackOverflow/Reddit is better. But if you just want answers to questions, a mailing list is the simplest thing in the world. If you have a lot of questions, you need to make a FAQ, and StackOverflow basically does that by sorting.
If you want to gamify your community engagement, StackOverflow/Reddit is better. But if you just want answers to questions, a mailing list is the simplest thing in the world. If you have a lot of questions, you need to make a FAQ, and StackOverflow basically does that by sorting.