Sure, that is largely true. But, to state that the formal register of Chilean Spanish is “probably one of the most understandable ones, accent-wise” of all available Spanish registers is, in my humble opinion, quite a stretch.
Goddamn, is that what professional news outlets sound like? It sounds like a YouTuber trying as hard as possible to sound cool or edgy. Dude, leave the coke for after the broadcast.
Where the announcer is actually overpronouncing while still keeping (expectedly) some elision. In your example, Boric’s formal register is closer to what one would usually listen.
> chileans are ok with people saying we don't speak well
I never claimed that, I am merely addressing your “one of the most understandable” statement.