For a long time, from the late 90's until roughly 2012, IE was the most popular browser. You had no choice but to work with it. If it didn't "work on IE", it didn't work.
Yea and people over exaggerated about it just like people over exaggerate things today like how hard CSS. The technology progress but people’s refusal to learn and desire to whine on the internet has stayed the same.
This is true, but the dominance of IE and its quirks, especially during the early 2000's, should not be underestimated. The browser situation, especially on Linux, was absolutely abysmal then.
I don't think flexbox really started being used until 2013 at the earliest, the comment I replied to was complaining about 2022 and a flexbox bug in IE. This 2012 thing doesn't seem to relate at all to the subject.
on edit: I know it was in WD in 2009 but I'm pretty sure it was around 2013 that people started playing with it. I think it started being popular in 2014-2015.
Here's a better explanation of the hostility towards CSS.
Nested flexbox had bugs in IE11, which wasn't end of lifed until 2022. The nested CSS in the article came out in December 2023.
CSS first came out in 1996.
The current state is much improved, but don't pretend there wasn't a solid 20+ years of sucking before that.