If I was racing in a race governed by UCI Rules,on a bike a sponsor paid for, I would absolutely be on discs, except for a TT.
There's a small advantage in wet weather, and no penalty because, the disc brake bike will still hit UCI minimum weight, particularly with my sponsor paying for the rest of the bike to be sufficiently light to hit the minimum weight limit.
Given that 98% of the races I do are not governed by UCI rules, i'll race my 13 pound bike with caliper brakes.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.