Parmandur
Book-Friend, he/him
A lot of players didn't realize thst it was a houserule, but thst doesn't mean their DM didn't know. All the instances I am aware of were adopting the change consciously. And it works with 5E as written! It doesn't even change a single thing if checks are being gated. And if people are gating properly...thst suggests they read the rules.The citation is all the memes, comics, and stories about nat 20s doing miracles, people correcting it, and other people being shocked that's not the rule.
WOTC made this rule because people played that way. And people played that way because they misinterpreted the rules since 5e isn't very clearly written. It's a direct shot against "natural language".