It’s not like it’s difficult. This isn’t the world of IE6, where a bloated Netscape 4.7 which failed to work on many sites was the only alternative. (Kant remember when KHTML - later konqurer - became more usable than Phoenix/Firebird/Firefox)
Problem was everyone had IE, websites were written for IE, activex, vbscript, etc
If it worked in Netscape fine, but large numbers didn’t.
On top of that, Netscape was a right resource hog.