Depends on what we had instead. The fact that Wintel systems had unlocked bootloaders was absolutely critical. But it could equally have been started on any system with an MMU. Certainly it's been ported to a lot of systems.
> Was it important to have a monoculture is what I'm wondering
Obviously this is just speculation but I would say, no. And the reason I say that is that Linux primarily took off on the server side. Mobile was quite a lot later.
On the server side it wasn't a monoculture. Sun was a huge player. When we were making the case for Linux, around 2000, it was presented as a cost play against Sun/Solaris.
Of course, it's fair to say that part of the reason it was a cost play was because Intel kit was so cheap and that was a direct effect of the desktop environment. But I'd contend that it wasn't a reaction to the Wintel desktop monopoly.
