CROSS-CATEGORY: 'Replace Slack' Became a Funded Category in 72 Hours — Buzz on Monday, PromptQL Today, Slackbot-as-MCP-Client as the Incumbent Answer

No Jitter (synthesized with TechCrunch Buzz coverage and Product Hunt PromptQL launch)·high signal

Block shipped Buzz on July 21 and PromptQL launched publicly on July 23 with $136M behind it, both attacking Slack on the same axis: agents as first-class, permissioned participants with shared context rather than webhooks in a channel. Slack's own answer is architecturally the inverse — turn Slackbot into an MCP client that consolidates other AI tools inside Slack, keeping the workspace as the host. The three-way split is the interesting part for builders: two challengers are betting the chat layer must own agent identity and memory, while the incumbent is betting it only needs to own the socket.