Oh those times. <script>document.createElement("table").appendChild(document.createElement("table"))</script> would crash IE, and some similar stupidities could even cause a BSOD as late as Windows 98.
(I think that was one such incantation, but if it wasn’t quite that it was close.)
Oh those times. IE accepted <table><tr><td><tr></table> whereas Nestscape demanded <table><tr><td></td></tr></table> and would just not render anything else - just blank grey
Humans loved it, when they had to type all this by hand, because missing /td would not kill your page.
Permissiveness won out.
I also remember the day JavaScript hit the net.
and all those "chat rooms" that did <meta refresh> to look live suddenly had no defence against this
<script>document.write('http://twistys.com/folder/porn.jpg')</script>
or alert bombs