The TVTropes Trope Finder is where you can come to ask questions like "Do we have this one?" and "What's the trope about...?" Trying to rediscover a long lost show or other medium but need a little help? Head to Media Finder and try your luck there. Want to propose a new trope? You should be over at the Trope Launch Pad.
You're essentially meandering into the fundamental concepts of tropes, Symbolism, Motifs, and other Lit. Class Tropes here-
Mushrooms make you bigger or smaller for instance, because the Catapillar's Magic Mushroom from Alice in Wonderland established a specific form of magic mushroom as a well-known concept, and then Super Mario Bros codified the connection in the context of video games as part of becoming a Stock Shout-Out based on another Shout-Out.
Why are mushrooms magic? They're strange things that grow in the woods and swamps. Some are delicious, some are poisonous, and some make you see strange things, and it's hard to tell which is which unless you're an expert like that old lady who lives in the woods and knows all about herbs and mushrooms and such. They also do that thing where they grow in circles and everyone knows the Fair Folk have to do with that, just like they make them appear out of nowhere after it rains or when the pantry gets damp...
You might be interested in tropes like The Coconut Effect, where narrative conventions become so ingrained that we assume they're reality, Forgotten Tropes that may leave behind only a symbol divorced from its origins, and Evolving Tropes with shifting meanings that can change perceptions of related tropes and symbols.
Edited by Scorpion451

In games there can be a disconnect between what an item is and what it does, or the connection may be only symbolic.
Keys and bombs and other simple pickups usually do exactly what they should do. In shooters, first aid kits giving you health seems pretty straightforward, if a bit handwavey.
An item like the burner cell phone in buckshot roulette is sort of "reaching" for something relevant. yes its very direct in that the phone allows you to receive contact from someone who knows a future shell's quality but like, why a cell phone? really its just a wrapper for that information. this is the "neutral" zone. beyond this we are getting to the point of the trope.
Platformers like mario world and celeste have "feather" items that allow you to fly - they activate a transformation of the player that /thematically/ relates to the item itself but its not like the feather itself makes you fly with it. it just grants you its relevant power
after this we get to things like roguelike items where the reasoning is a bit strained - in the binding of isaac, different kinds of mushrooms grant different abilities like making you big or small or know more of the map. in balatro, there are planet cards which somewhat relate to what hands they influence
i struggle to think of further category examples but in some games the relationship between the item and its effect is almost not even there / not there at all. in SCP lingo, these items are "an x that does y". and when you look at games where there are just a lot lot lot of different themey items this sort of scale feels more relevant, as you stray from arcade style item design you see the like, difference between when the theme connects vs when it doesnt / when it connects to the game or not
so i guess i dont know which part of that is the trope but theres my spiel
Edited by TheJonyMyster