My potentially controversial take is that metagaming is neither good nor bad. A metagaming problem is really just some other problem that rears its head through metagaming.
You can metagame and be a good player. It’s like doing improv with dramatic irony. If you’re prioritizing the gameplay and everyone’s enjoyment, it’s a useful tool.
If you’re using it for the personal advantage of your character, though… that can also be fine. Some old-school games, especially dungeon crawls, are like strategy games testing the players as well as their characters.
It’s when there’s a disconnect between how people are playing the game that you get problems. If someone wants to play a strategy game while others want to play improv, and they’re not thinking about what kind of approach is appropriate and when, that you get issues.
I do get the meme, but I can’t really think of a way to hide specifically the result of a failed wisdom save from a player.
Like how would you tell a player sometime like “You feel like Alric is a wonderful person despite the corpse he is looming over” without it being very obviously a failed save against charm person? Same for basically any other enchantment.
Other spells with wisdom save are even more obvious by virtue of taking damage, or being turned into a cow.
Detect thoughts and dream are the only two I could find where rolling in secret works for wisdom saves.
This is cool in theory, but kind of annoying if you are trying to modify the roll with something like Favored by the Gods from Divine Soul Sorcerer that specifically can activate if you fail the roll.
You add an additional 2d4 to your attack/save that fails.
I’m not sure if ANY other dice modifications work after knowing failure, but I know this one does. I know when I play divine souls I always like to save it for those random Int/Wis saves that’ll get ya.
Fortunately Metagaming Bob isn’t at my table, but we are going to try this out with death saves
I just had an absolutely terrifying idea for death saves: Literally drop dice in a small container, for everyone to see. But do not remove the die afterwards, just leave it in. Every new death save, toss another one in, potentially hitting the previous dice and changing their outcome as well.