I wouldn't be entirely surprised to find out that the change was motivated by issues with certain LCGs (i.e. the asymmetric ones) and applied to X-Wing as part of an unthinking 'one size fits all' approach.
That's almost certainly it as far as I can see. They added a rule requiring you to sleeve alt art cards so people can't identify them from their backs a while back. Whoever put that in didn't even read the rules of X-Wing in the first place, let alone know them well enough to write tournament rules for it.