The real question is why there isn't any official API that details the nature of the danger. You shouldn't have to scrape Telegram to figure out the type/speed of the air assault weapon, and the likely time on target. BTW, also check out Kropyva, it's like Uber for artillery strikes. Very helpful with deleting Russians.
Any single API for this would be constantly attacked. They're distributing the attack surface by using other services.
Also, nothing stops you from redistributing the structured messages through multiple channels.