Your snarky strawmen address none of my points and will not be responded to.
I'm very curious how you think user registration and an API make for a less flexible system. What exactly are you wanting to do with Slack that the existence of an API and a registration system prevent you from doing or get in your way of doing?
And considering that Slack is generally accessed via HTTP, it kind of makes sense for it to have a sane HTTP interface, something for which every language has decent tooling for...
I'm very curious how you think user registration and an API make for a less flexible system. What exactly are you wanting to do with Slack that the existence of an API and a registration system prevent you from doing or get in your way of doing?
And considering that Slack is generally accessed via HTTP, it kind of makes sense for it to have a sane HTTP interface, something for which every language has decent tooling for...