I honestly think this is a bit of a generational gap. I grew up in the 90s and remember when "PCS" phones (the kind that started the whole personal cellphone thing for the masses) did not have text messaging. Then, later, some did, others didn't.
Eventually, every phone and carrier supported SMS. IMO, that's partly because they charged per message. Shortly after that, some carriers offered a friends and family texting plan, where you could set a small amount of phone numbers (I think 5 was common) that would be unlimited texting, everyone else you texted was some small amount per message.
Pretty quickly that was followed with unlimited texting plans.
Almost immediately after that long form texting, aka MMS was introduced, but it was problematic from day one..... You could also send multimedia over MMS, like pictures.... They were compressed to hell, but it worked.... Sometimes.
Everything went RCS and data driven chats after that.
The key point I'm driving at is that early texting, aka SMS, was limited to a maximum of 160 characters, which might just be able to contain the jist of a sentence. If you grew up before sms became a thing, long form may suit you better than alternatives. If you grew up with SMS, you probably have a learned behavior that text based messages should be pretty short and to the point, so many small-ish messages are probably required.
I am excited to see what happens with those that didn't have to limit their messages to 160 characters, grow up.
I'm more or less on the cusp of the technology. I was subscribed pretty early on in my youth, so I'm kind of both but also nether. Anyways...
In my experience the biggest reason texts were short wasn't the limit but the fact that we grew up having to text on a telephone keypad so it took forever.