But those tools were hard for laypeople to use in 1995. Sure, Windows now had a web browser and email program but you still needed an ISP and the email client was confusing to setup. Hell, their own Microsoft Network service was hard to figure out; one phone number to connect to the proprietary service and a different one for the Web (which never connected for me).
It was much simpler for users to put in the AOL disk and stay inside their walled garden - both conceptually and technically easier for laypeople.