AFAIK, the MACs at the time was all point and click. Building GUI applications is not easy. Borland's IDE was text base, making that a GUI may have been to expensive based upon the amount of $ that could be made.
Also, most MAC people considered themselves Artists, not developers. Most individual developers (all) were hacking on DOS at the time. So that may have played into it too. To me, it is all about potential revenue vs expense.
I wonder how much games played a part. In my case, deep down all I wanted to do is just play games. Ataris and Amigas had nice games but at one point the PC just blew their doors off. The Mac was a sad non-contender you used in your print shop to design calendars.
My suspicion from early in my career is it was people that came from IT who just assumed that 'MAC' was an acronym for something, like pretty much everything else they dealt with, as opposed to the shortening of the proper noun 'Macintosh.'
Also, most MAC people considered themselves Artists, not developers. Most individual developers (all) were hacking on DOS at the time. So that may have played into it too. To me, it is all about potential revenue vs expense.