That might just come down to the usual differences between Python and Ruby. A Python programmer would likely appreciate an explicit call to `subprocess.run`.
As an experienced Ruby programmer I imagine the code you provided looks like a no-brainer. To a Ruby neophyte the backticks, $? sigil, and .to_i method don't strike me as intuitive (but maybe they would be do someone else). We may just have to disagree about the nicety of syntax.
As cle mentioned[1], the strongest criteria is
> what would the majority of people on the team prefer to use?
and I'd agree that ultimately that's what makes the most sense.
The back-ticks and $? are shell standards so I would expect those to be familiar to shell scripters. I agree that if one knows nothing about any of the languages then neither is much better.