This is a really smart more on their part to get people to stop doing precisely this, and getting them to pay money for RH. Pepople who are not willing to pay (me included) are now rightly annoyed, but we were never their customers in the first place, so we don't really matter.
Now? “¯\_(ツ)_/¯“ Probably Debian.
I’ve always used CentOS for clusters, but part of the reason for that is that there are some research packages that support RPM installation, but not deb. At least this gas historically been the case.
If a large amount (maybe even a majority) of users have to switch away from CentOS and RPM packaging, I think we’ll see an acceleration away from RPM as a default option.
So, in that way, I think we do matter, but just not on the balance sheet.