It isn't just the supply that gives something a value, it is the demand as well.
Supply doesn't really affect Bitcoin's price that much as it is always accounted for, because it is predictable without a doubt.
It is the demand that affects it's price the most. The demand decreased for whatever reason (some sort of panic selling probably) and therefor the price fell.
correct.
the supply has been a known factor since day 1. it has not changed, everyone knew and knows the supply. but the demand is the variable.
demand affects price more than supply.
You are confusing
market supply and
money supply. Both use the word "supply", but they have very different meanings. The
money supply is a number. It is the number of bitcoins in existence. The
market supply is a curve. It shows the price necessary to motivate people to sell any particular number of coins.
Market supply is what is referred to by the term "supply and demand".
Of course the two are related, as the money supply affects the market supply. But, it also affects demand, which is why your argument is weak.
To strengthen your argument you would have to show that the demand curve is steeper (less elastic) than the supply curve, so that a shift in the demand curve would affect the price more than a shift in the supply curve.
80 percent bitcoin has been mined and in circulation so bitcoin is in abduant circulation there is no scarcity
"Scarcity" is a term in economics that generally means "finite" or "limited". It does not mean rare or hard to find. Gold, oil, and bitcoins are all scarce because the amounts are limited. Air, water, and food are not scarce because there is an unlimited amount. Air and water are recycled and food is grown.