Slack exists largely because IRC was insufficient. It didn't natively support channel history, search, etc. For AI agents to flourish, Slack has to either truly open its network with a protocol or eventually be replaced. I'd like to see Slack embrace an AT protocol-based chat system, which then apps like Buzz could implement. Then users could log in with domain handles like @yourname.com, and agents could use handles…
Chat is also not a great modality for the PDS/ATP, Roomy learned this and is building a dedicated protocol and bridge.