Like, hacker news almost allows anonymous posting because the account creation is so simple.
That doesn't make it impossible to have anonymous accounts, but it is a high tradeoff decision and likely a defining one.
I think it's more applicable for sites that have somewhat more objective and/or legible goals. Wiki-ish sites, for example. If there's a lot of free form discussion... anonymity is probably a bad decision for the site owner.
Allowing individual subreddits to enable anonymous posting lets the market decide if the pros outweigh the cons. (If the subreddit has a history of bad moderation, ban the subreddit)
I feel like giving communities more options in customizing the algorithm that dictates the discussion is powerful.
For example there were multiple "name a product" contests raided by trolls- because nobody moderated the inputs.
HN has its own problems: the "flag" feature is abused by brigaders to censor content.
"Throwaway accounts are ok for sensitive information, but please don't create accounts routinely. HN is a community—users should have an identity that others can relate to."
Gab, the free speech social network, deals with this topic a lot... and likewise does moderation with a flagging system, volunteers, group mods, and site mods. The community is far larger, but our policies are much simpler to compensate.