This is conflating two issues identified with Microsoft's practices during this time. Both of which got them in trouble. Microsoft abused it's dominant position

This is conflating two issues identified with Microsoft's practices during this time. Both of which got them in trouble. Microsoft abused it's dominant position in the PC OS market to (A) lock out competition in the OS market and (B) gain footholds in other markets and extinguish competition (such as for the web browser market). It's a strained argument to say that if they hadn't have put the OEM agreements in place that they would've been completely unchecked by the antitrust authorities in the browser market.