Not all developers work together.. You have competing developers from other Alt coins, who would gladly expose any backdoor or fulnerability like that, to boost their own coin.
You also have cryptography experts with no interest in Bitcoin, who are hired by countries to secure their networks. If a specific country, say China wants to accept Bitcoin as a payment method, they would outsource to experts in the field, to test it.
These experts have a reputation and a income to protect, so they will make sure, that they give 100% correct information to their employers.
Would you as a Bitcoin Core developer, give anyone ammunition, by creating a backdoor, and risk being exposed and losing your income and reputation?
Does that answer your question?
That's just plain stupid.
Why would anyone waste their time trying to find backdoors or vulnerabilities on any other coin instead of using their time more productively by improving their own?
It's acctually very simple...
Bitcoin is sitting comfortably at the top, with no real competition. {Price & Adoption} If you are the competitor, and you can expose such a backdoor, it would drive people away from Bitcoin and possibly towards your currency. {You would obviously use that as ammunition to boost your own coin}
Why is it so difficult to understand that?
The code is not that complex, that it would take a expert weeks to analize it... they most probably evaluated it anyways, when they developed their own coin.
