I think the NT and OSX updates were absolutely required due to architectural reasons which impact security, 98/ME and MacOS 9 just simply weren't suited to type

I think the NT and OSX updates were absolutely required due to architectural reasons which impact security, 98/ME and MacOS 9 just simply weren't suited to types of threats on the internet (no support for dropping process privileges, file permissions, cutting direct access to hardware etc.). If you think XP is bad in 2010, think what Me would be like if widely installed still, one program crashing the whole machine, boot sector viruses etc.