I had the exact same opinion, on top of that, I thought that it doesn’t make sense to build something if someone else is already doing it since > 1 year.
I then reminded myself that most audit companies are not providing great audit services and I translated that into the option that the corresponding tools might not be great either.
Started working on something and so far at N=6 it turns out it wasnt really hard at all to build something which is around 10x better than the rest.