I really dislike it too.
I think it might be adults ignoring established grammar rules to make a statement about how they identify a part of a group of AI evangelists.
Kind of like how teenagers do nonsensical things like where thick heavy clothing regardless of the weather to indicate how much of a badass them and their other badass coat wearing friends are.
To normal humans, they look ridiculous, but they think they're cool and they're not harming anyone so I just leave them to it.
can't imagine getting this riled up over lowercase text. some serious fist-shaking-at-clouds energy.
it's meant to convey a casual, laid back tone - it's not that big of a deal.
make a statement about how they identify a part of a group
That’s what it is. A shibboleth. They’re broadcasting group affiliation. The fact that it grates on the outgroup is intentional. If it wasn’t costly to adopt it wouldn’t be as honest of a signal.