There's also a new player called diversion (diversion.dev) which I think may be a YC startup? Anyway it takes a different approach of being more like Google drive but bringing in VCS behavior making it more indie and designer friendly.
Today your statement is a little too ambitious but I agree with the overall point that the inherent effort based moat in SaaS is mostly gone and now it is really about personalizing your own.
The most common counter-argument that I've seen here is " Yes, but no organization wants to manage all of their different operational tools. They would rather just outsource that responsibility to third-party entities".
I'm not sure I fully agree with that counter. Because agents can be viewed as third party entities in some sense. If not today then maybe soon.
This is my immediate concern as well. Sam said in an interview that he sees "intelligence" as a utility that companies like OpenAI would own and rent out.
I do like how in some MacOS examples we see icons for some of the more important or commonly used menu items, but not the others in the same list. The absence of icons has meaning ("it's likely not what you want")