I and everyone I know turns it off. On many platforms and in many cultures, capitalization often implies Solemness or even rudeness in 1-on-1 conversations, and otherwise comes across as being out of touch in other kinds of communication.
It's not directly rude, it's more like a serious tone of voice. But it only works like that when used unnecessarily, like in chat or IM where the message boundary styling doubles as a sentence boundary.
Using the chat/IM style outside of that context just doesn't work and looks really odd, like it's obviously someone who didn't learn those norms and is now mimicking them without understanding them.
That's different from a "serious tone of voice" though. Think like the way a parent might start talking to their kid when they're angry but not yelling, with something like "You better get home right now."
Or another example: "Call me" is a just a regular "let's chat about something", but "Call me." is "something bad happened I need to tell you about, so prepare yourself".
Interestingly, you're actually partially doing what I described on 2 of your 3 messages in this chain - you left out the last period because HN formatting makes it obvious where the sentence ends. So even if this norm did apply here (it doesn't really), you're not using the serious tone of voice.
This is interesting. I didn't realise so many people disable it. A lot of what you're saying is completely backwards to my life experience.
For me and I guess most people I communicate with on e.g. Whatsapp. "Call me." is normal, expected, everything is fine, just need a phone call. "call me" is more like something has gone so horribly wrong (or someone is so incredibly pissed off) they've lost the ability to communicate normally. I wouldn't be offended, more like concerned.
Wow then I guess everyone finds me very rude. I capitalize, use correct grammar and spelling to the best of my ability in text messages just like any written communication. I find it rude when people don’t as I interpret it as they don’t even care enough about our communication to take the small effort to make their writing easy to comprehend and understand!