> 1998: Many major companies such as IBM, Compaq and Oracle announce their support for Linux.

-- https://en.wikipedia.org/wiki/History_of_Linux

It was all about Solaris, AIX and HP-UX for .com businesses.

I was there, our Linux deployements were only used internally, we never sold those workloads as UNIX targets on our product.

Back then I went with Debian, but I agree - the early scale-out crowd went mostly with Red Hat. Back then there was a lot of companies still doing scale-up with more exotic hardware with OSs like AIX and Solaris.

nope.

the first enterprise Linux was SuSE on s390, then came RH on x86 and then suse there as well. but RH marketing was better back then already :-D