Browser updates were slow back then, even for Netscape, so this didn't matter at all.[1]

I have never once heard anyone complain that the reason why IE6 was bad was because of "slow updates because it was part of Windows". It was bad for many other reasons, but not that. Microsoft released plenty of hotfixes outside of the normal Patch Tuesday cadence.

[1] https://sillydog.org/netscape/verinfo.php