RedHat, like all other distros, was initially a boxed product- CD ROMs- and support, consulting and custom work was available, arranged via email and phone call. Eventually RHEL was set up as a subscription- not SAAS- with stable releases (of CD-ROMs) and enterprise tier (phone) support. Sure, people shared links and experiences over USENET but there was no "growth hacking" in 1993, not in anything like its present form.
The world is completely different now. There are zillions of more modern examples of open source/open core/saas/support business models, free vs enterprise pricing, etc etc.
RedHat was a 1 of 1, and that ecosystem is gone. Find another exemplar.
But that's not what Redhat actually was. Redhat was a support company. Corporations buying per seat and per server support contracts is what made Redhat a business. Having a Linux distribution was a way of productizing Linux support. There was a clear value proposition to an enterprise customer base. Redhat wasn't a guerilla operation.
And/or talk to Walnut Creek CDROM, inc about getting in their monthly linux cd bundles. These are the people that ran ftp.cdrom.com.
Actually, that's not really early users; that's 3 years in. In the early days, just kind of work on what Yggdrasil users are complaining about, and advertise in their news groups maybe?
[1] like this one https://www.ebay.com/itm/225617084070
They were here very early on, had a great initial onboarding experience and features packed.
A modern equivalent in their own space today maybe would be Notion - created a category of their own, dominated it and branded themselves really really hard
IMHO, their reasons are irrelevant today and you shouldn't use their path as a guide.