Is there any use case that's actively deployed, where DANE is being used? I tried to look up use cases that exist today, and it seems like it's "people who run their own postfix/exim servers", 2 niche email providers, and... GPG?
I don't follow DANE but I think support among the mail community is wider than you suggest unless Microsoft Exchange Online is one of the niche email providers you're referring to.
It can also be quite easy. Buggy complicated Route 53 and self-hosting with a buggy bespoke solution aren't the only options, but they are the only kinds of DNSSEC failures I've seen on the HN front page.
The only failures you see on the HN front page are the ones that occur to gigantic companies we've all heard of, with huge networking teams and all the advantages you can ask for in getting DNSSEC working. When random small shops fall off the Internet because they broke DNSSEC, nobody cares; it never makes any front page anywhere.
I would dispute that the entities that make the HN homepage have all the advantages. Off the top of my head, Slack clearly did not have in-house DNS expertise though they could have if they valued it, and '.nz' seems to be run by at best a skeleton crew.
