Given the source, I'm skeptical it's not just a troll, but found this explanation [0] plausible as to why those vague spam text exists. If true, this trolling helps the spammers warm those phone numbers up.
There are stories of people replying STOP to spam, then never getting a legit SMS because the number was re-used by another service. That's because it's being blocked between the spammer and the phone.
(Edit: It's relevant that STOP didn't come from the TCPA itself, but definitely has teeth due to it)
https://www.infobip.com/blog/a-guide-to-global-sms-complianc...
Again, no clue if this is true, but it seems plausible.