They probably mostly don't need to be.

Most SaaS companies are not doing anything particularly innovative or novel. Most of them provide value via putting in the work to glue together several other APIs, automating something that previously was harder to script/automate, or simply applying an idea that another company pioneered to another market segment: "It's like Theranos but for barbers!"

These use cases are generally so typical of the technology being used, that LLMs can do a lot of work to script things and it's usually pretty easy to QC.