There are many ways to answer that. First, people all over the world drink from all sorts of things - ceramic bowls, wood boxes, skinny glass tubes, fat bowls. So you can drink from whatever makes you happy and it's fine
It's always about your nose, which is how you sense most flavors. Your taste bud only senses sweet, salty, sour, those basic types of things. Your nose is what senses "roses" and "tobacco" and so on. So a key function of a cup / glass is to help your nose smell things well. A second function is to minimize alcohol fumes so your nose doesn't burn and you can actually sense the flavors
Glasses like "Riedel" work carefully on that task. Different types of wines have different types of aromas and the glasses help balance those aromas to your nose while holding back the alcohol.
It's easy to see for yourself if you personally care. Get your normal glass or mug or whatever. Then buy just ONE Riedel glass (or borrow one from a friend). Pour your favorite wine into both. Taste both. Can you taste a difference? Which do you prefer? It's all about how YOU enjoy the flavors.