Look at how much they are spending. Think about how HN cheered Tesla's innovation in disintermediating vehicle sales by selling direct. Now think about OpenAI or whomever selling directly to enterprises. It's the same proposition:
"That Enterprise SaaS startup adds a markup to the AI that is powering your app."
Again, this is only IF the AI-vangelists are correct that some startups will collapse to a solopreneur. I am not sure that those same startups won't vanish entirely.\
———
There are some high-stakes apps where Enterprises prefer vendors for extrinsic reasons. For example, some apps must have certain certifications, and in a vibe-coded future, the cost of certification could exceed the cost of development by multiple orders of magnitude. And it needs to be kept up. Another example would be apps where for liability reasons, it is helpful that there be an "industry standard."
But lots and lots and lots of apps are not nearly so consequential.