3Com made an Ethernet card for the Mac in the late 80's. 3+File/Print/Share existed for the Mac as well. I knew people who worked on it. Claris Software was initially an independent company selling software for the Mac.
PowerPoint was initially Mac-only (1987). It got bought by Microsoft so they could port it to Windows.
Claris was originally spun out from Apple so that MacWrite/MacDraw etc would not be seen as competing with third-party developers with an unfair first-party advantage.
> So yeah, Macs were around, but hardly ubiquitous.
And I'm not claiming they were ubiquitous, just that they weren't so niche you'd only see them in schools or on the desk of a graphic designer. They had something like a 5-10% market-share in the US. Anecdotally, that played out in my community as far as I can tell (e.g. 1 in 20 kids having a Mac at home sounds about right). You didn't have to go anywhere special to buy them, but the store might have 20-30 PC models on display with 2-3 Macs.
PowerPoint was initially Mac-only (1987). It got bought by Microsoft so they could port it to Windows.
So yeah, Macs were around, but hardly ubiquitous.