Why have dev`s made Circulating Supply so large for their coins. Some are in the tens of billions & even trillions.

Why didn't they just follow Bitcoin at 21 million, or just limited to 100 million or so?

The reason i ask is the price movement over $1 on some of the coins with the larger supply will always be limited. On coinmarketcap there isnt any coin out there with a CS in the billions more than $2-5 max. The simple reason is the marketcap - price x CS. Your not going to get a bigger marketcap than BitCoin for now anyway.