That is not why the rule was originally put in place back in the 1800s when baseball was a completely different game. It is a hold over from a game that doesn't really exist and should have been removed just like other rules of that time. Like a fly ball could be caught on a hop for an out, among others.
I assume the rule was put in place on the reasoning that all outs must be achieved by a catch or a tag. Why is that outdated? Not necessarily disagreeing, but not sure I follow the reasoning that it's obsolete.