Sometimes wins fiat sometimes wins crypto. For a more stable value is fiat which its value decreases or increases slowly comparing with bitcoin or other coins which the value increases or decreases very fast, check the most recent price of bitcoin and you can see how far has dropped, bitcoin is good, fast enough and cheap to use but the value is not as we want.
One Bitcoin equeals one Bitcoin no matter what price the illiquid exchanges trade the Bitcoin for. Not many people trade at these exchanges, thats why any suden activity in trade can move the price a lot (up or down). But wait longer periods and average out and the short term price moves from illiquid markets are not big issue anymore - to accomplish this you might buy or sell small sums at regular intervals regardless of price for longer interval, then you get much fairer price from this averaging. But obviously if you dont need to buy or sell, you still holding the same amount of Bitcoins (or percentage of all Bitcoins) no matter what.