My only caveat is that if I was playing a game and I queried one of my opponent’s rules and they tried to show me a wahapedia entry, I wouldn’t be satisfied with that.

Conversely, GW's rulebooks are generally so full of errors, and will be updated so many times over an edition, that having a physical copy of the rules is usually even more useless than looking at Wahapedia which actually gets updated as errata is released. Straight up I'm not wasting my time looking at your rulebook if there's some scuffed rules shit happening. I'm gonna search DakkaDakka/google because I want the correct answer, not whatever half-baked garbage made it to the printer's in time and has since been substituted three times in downloaded documents.

Whatever issues there are with currency and accuracy of Wahapedia are magnified significantly if you limit yourself to GW's frankly pathetic rules offerings and having used their new app this doesn't look like it's going to change anytime soon.