linux is holding its own just fine on the enterprise server market and a lot of those servers do run redhat because out of band security patches and general support = a ton of equity.

but the achilles heel for rhel is just that once you get into the real talented sysads / devops, they generally prefer debian/ubuntu and its basically a culture/politics thing.

also fun fact speaking of red hat vs microsoft, windows 10 has a full fledged native linux layer available as an elective install. i find that fascinating and wonderful.