That site, along with several similar ones, is banned on HN because it has been the source of too many low-quality posts and too much promotional behavior.
I post stuff on dev.to and am surprised to learn that many people on hn consider the entire site spam.
Just scrolling through the first page of links there it looks like a whole lot of clickbait garbage or overtly scammy looking shit.
I just ignore those since dev.to is blocked on the network here at work...
They're... Not? I looked through the 20 most recent links and 19 worked fine. One 404d but it was an article submitted 3 months ago.
Maybe dev.to was flubbing when you looked?