I think that is an unfair accusation.
I've been coding for over 20 years, and I have only had to enable UTF8 to cover all corners of use cases (web based data/content) to special characters. I work with companies in multiple foreign countries, and my biases are irrelevant to technically working systems.
Where in the alphabet does "ö" or "aa" go? Well, it depends on the language AND the word.
Is ø the same as ø? Unicode can encode it in 2 different ways, so you need to normalize all encoding before comparing.
Is ø the same as o when searching? For Americans it is, for others not.
Never implemented a search function?
These aspects can easily creep into an app without you even noticing. Saying "I haven't seem them" is not proof for them not being there.
E.g. web servers had some surprise security bugs because they didn't think about overly long utf-8 codes.
I implemented single fields for personal names, single textareas for addresses and some very basic content format selections and collation and my simple solutions have solved _all_ of my customers needs in these areas.
It seems to be some bizarre assumption that _everyone_ has a bad experience because some code wasn't done they way they would do it. It's absurd to be accused of something that has simply not been a problem for my users.
This is where the accusation crosses into unreasonable for me.
Could there also be bias in the statement "ASCII is not good enough."?