SaaS is too unstable for semiconductor manufacturers to rely on. They would want a locally-installed, stable X.Y.Z implementation.
If you are running a serious fab you already have AMAT equipment anyway and there's probably good reasons to get the industry standard AMAT MES software.
Realistically, this software will probably continue not to exist because there are not many target customers in this "mini-fab" segment, and they are uniformly poor. That's not a great outlook for sales. If your software is any good, you want to market to the same segment AMAT does and go for the multi-million $ licensing fees.