Tim Berners-Lee who is creator of WWW said as following:

“Anyone who slaps a ‘this page is best viewed with Browser X’ label on a Web page appears to be yearning for the bad old days, before the Web, when you had very little chance of reading a document written on another computer, another word processor, or another network.”

The heart of www is to enable everyone to have freedom to read any document regardless of computer, operating system, browser.