Yes, as others have pointed out already.

Partly you have enterprise software from big vendors like Dell or Alcatel that is packaged for RHEL.

You have hardware vendors like Dell and HPE who only offer support for supported OS. And yes I know CentOS is not a supported OS but its binary compatibility with RHEL meant you always had the option of migrating it to RHEL and get support.

Also I have government clients who require SLA with support contracts on the systems. In those cases, given the arguments above, including years of experience, RHEL has more weight than Canonical or Suse.

And besides all that, I'm actually a SElinux fanboy. I've had a lot of upgrade issues on Debian in the past and some clients even require certain yum features like history and rollback for patching.

That said, I tend to use whatever is the right tool. I tend to look at how a service is designed to decide which distro to use. Of course I prefer homogenous environments but for example I'd rather put a stable CentOS as a webfront/TLS terminator and a bleeding edge Fedora as an application server for things like Node or Python.

So in the future I would not rule out using Debian Stable as web front instead.