That's not the threat model. The threat model is that they won't have to - at some point which may not be right now. End users want to get their work done, not learn UIs and new products. If they can get their analysis/reports based on excels which are already on SharePoint (or wherever), they'd want just that. You can already see this happening.
For one thing, the threat model assumes customers can build their own tools. Our end users can't. Their current "system" is Excel. The big enterprises that employ them have thousands of devs, but two of them explicitly cloned our product and tried to poach their own users onto it. One gave up. The other's users tell us it's crap. We've lost zero paying subscribers to free internal alternatives.
I believe that agents are a multiplier on existing velocity, not an equalizer. We use agents heavily and ship faster than ever. We get a lot of feedback from users as to what the internal tech teams are shipping and based on this there's little evidence of any increase in velocity from them.
The bottleneck is still knowing what to build, not building. A lot of the value in our product is in decisions users don't even know we made for them. Domain expertise + tight feedback loop with users can't be replicated by an internal developer in an afternoon.
I really have difficulties seeing AI as anything else than yet another type of machinery. If your argument is "but it's replacing ALMOST ALL human labour" - well, the same argument was valid for tractors a hundred years ago (when almost everyone was employed in agriculture).
this is only true for larger multi-stage funds who compete with each other, not for Seed or Series A-only funds