It was though. You are living in a bubble. For five years all I ever heard was "You gotta switch to Ubuntu! Windows is awful!" Except this is when I was still using Windows XP, so from my perspective Windows wasn't awful. It was just out of date. From 2006-2011, that's all I ever heard was Ubuntu Ubuntu Ubuntu.
ubuntu's early popularity had nothing to do with it being 'lightweight' (because it really wasn't).. but rather simply because it was 'new' and 'easier', and everybody was jumping on that bandwagon. that's it.
xubuntu came around with dapper (june '06) and quickly became a popular recommendation for older or low-spec hardware. ubuntu itself was never that choice. ever.
I'd say around 3-4 years ago it started shifting towards Mint.
linuxmint has been going strong longer than '3-4 years'. a lot longer.
my PC hasn't been updated, or changed in any way since 2023.
I don't even update firefox. I'm running 133.0.3. I think firefox is somewhere near version 200.
it is your choice to ignore updates. you know your software is out-of-date and vulnerable.