Most mountainbikers will be in baggies. It’s just more comfy and the pockets are good for storage. A majority of those will have bib shorts or lycra shorts on underneath as a chamois still goes a long way.
Tops are looser generally for comfort and being cooler (heat wise) - MTB is slower so less tight fitting clothes allows the clothes to breathe.
That being said, XC people are generally in lycra. Nothing wrong with that at all.
What is wrong is lycra and knee / elbow pads / full face helmets. Don’t be a Joey!
Peaks on helmets are for a few reasons - 1) they just make the helmets look cooler, 2) the provide shade over your eyes, and 3) they aid in deflecting branches and bracken away from your eyes. But mainly 'coz they look cooler
MTB apparel has evolved to be fit for purpose. It’ll handle the falls. It’ll handle getting snagged on branches. It’s functional.
Get yourself some understated gear - you don’t have to look like a Fox advert! Actually, that’s another reason for a lot of mtb existing originally - people didn’t want to be a Banesto ad!
Heaps of different styles of wear out there - I’m sure you’ll find something you like.
But no knee pads and lycra…capisce?