A lot of people out there claim to know Linux, yet few can prove it. OTOH, if they gain a cult following with lots of people using their stack, those people mig

A lot of people out there claim to know Linux, yet few can prove it. OTOH, if they gain a cult following with lots of people using their stack, those people might become more familiar with their stack than most Linux people are with theirs. They could grow a captive base of prospective hires. That's not the big concern though. The big concern is whether vendor integration and certification becomes a stumbling block. You can hire any monkey to write good-enough code, but that doesn't give you millions in return. Partnerships with vendors and compliance certifications can give you hundreds of millions. The harder that is, the farther the money is. A totally custom, foreign stack can make it harder, or not; it depends how they allocate their human capital and business strategy, whether they can convince vendors to partner, and clients to buy in. Anything very different is a risk that's hard to ignore.