It wasn’t intentional sabotage.

(a) MS expected to make money on the Mac, and did for many years with Word and Excel (well before they were bundled into Office), among others. The best versions of Excel and Word were on the Mac for a long time.

(b) Microsoft eventually released a QuickBasic for the Mac that was capable of producing apps with a real Mac UI. IIRC, the IDE wasn’t very good, but it was capable enough at the time.

Killing the ability for users to easily create GUI based programs certainly counts as platform sabotage in my book.

There was no Windows yet on PC, and Microsoft Basic for Mac gave you almost no ability to create programs that took advantage of the Mac UI. You were limited to creating text based programs on a system that was all about having acess to a graphical user interface.

It's pretty easy to see why Microsoft didn't want Basic programmers on the Mac to be able to do more advanced things than Basic programmers could do on DOS based computers.

What they did makes sense if Microsoft thought BASIC was important for the Mac, and that their BASIC could satisfy that important need.

If they didn’t think BASIC was important, or if they knew their implementation was rubbish, makes far less sense.