It's the statistics.
They suggest that teams which kick the ball away win more games.
It is, of course, misleading.
In the Ashes Tests recently, England's statistics showed that Travis Head was 'vulnerable to the short ball', so they bounced him, constantly.
If all you get is bouncers, you'll probably get out to one eventually, but not until you've got a good score, as Head demonstrated. He also demonstrated that he'd get out to well pitched up bowling if ever anyone bowled it at him. There was a place for bouncing him, but with no variation, he was well set for it.
There's a place for kicking in rugby:
a) to clear your lines or gain significant territory
b) as an attacking move if you're likely to score that phase by doing so
c) if you're about to get thumped into touch and concede a lineout anyway
d) maybe as a surprise variation
I'm open to other suggestions, but will not be including "but, muh statistics" or "we're in the opposition's 22, it's a great idea to kick the ball away aimlessly" on the list.