They mean Microsoft daring to give Internet Explorer away for free and integrate it into their desktop shell, as it undercut Netscape's business model at the time: to convince ISPs that their customers needed Netscape--which cost $40 (at a time when you didn't buy software "for life": later versions would have upgrade fees)--and so their Internet subscription price should include the cost of Netscape (which you might recognize as Microsoft's business model for getting PC manufacturers to license Windows; hell: Netscape was even refusing to implement CSS or open their DTDs while throwing in tons of Netscape-specific extensions and features in the hope of achieving lock-in on their platform! both of these companies sucked and neither was sympathetic). https://vimeo.com/310654342
Operating Systems didn't always come with a browser. We used to have to go to a store and buy copies on floppy disk or get a copy from a friend or download from a BBS. Hell, sometimes we had to install TCP/IP support since it wasn't part of the OS. So when MS included a browser in Windows the groups that also made browsers cried foul. Downloading and installing software was a painful thing and a real barrier to adoption.
