the price will go up because more demand for that product exists than supply.
It's literally how prices on everything work, but it's not that simple. I highlight the reason why bitcoin won't go up until the economy will get rid of the existing problems and inflation is one of them (and the big one).
If demand for bitcoin falls, it might result in a rise in price as people sell their products at a reduced cost.
No, if demand goes down and supply up, the price goes down as well.