Plus, it's likely that if someone where to create a fake bitcoin, the developers would know amd the market would feel it if suddenly there's a flood in supply right?
There would be no flood in supply.
The bitcoin source code is entirely open source. I can take it and launch a fake bitcoin clone, maybe called Bitcoin Scam Version (BSV) or Bitcoin Counterfeit Holdings (BCH), tomorrow. None of the bitcoin nodes will pay me any attention, none of the miners will care, no wallet or block explorer will support my coin, and none of my transactions will be compatible with bitcoin. I can try to "flood" 21 million new coins in to the market, and they will go nowhere because they are a different coin which is completely worthless.
If someone tried to create a real bitcoin transaction which created a flood of new bitcoin out of thin air, they would need to convince the majority of nodes and miners to accept their invalid transaction, which is obviously never going to happen.