Not even close. If you remove Safari from OSX, the OS still works. If you take IE out of Windows, the cracks appear.
For years ,anyone who wants to has been able to download or even have sent free to their home or business,Ubuntu linux on CD.
As much as I dislike some M$ practices,the EU is trying to close the barn door after the horse is out!
IF M$ had been prevented from providing any web browsers,Netscape would probably be still dominant.
AOL actually killed off Netscape,after buying it.