Why is there no decentralized Bitcoin trading API? Since nobody has answered me the last 30 times when I asked for decentralized Bitcoin trading APIs, I can pretty safely conclude that it just doesn't exist. So that's why I now ask why this is.

Don't you think it's ironic that Bitcoin, the decentralized currency, has no means of trading it with other cryptocurrencies, or with some kind of token, or with fiat, or in any way, without using one of those centralized "exchanges" which all force you to give up privacy completely and send them photo id of government ids and stuff like that?

It should go without saying that such centralized exchanges, with their "KYC/AML" demands, defeat the entire point of Bitcoin -- to not be harassed in this manner. Many of us cannot even do it, even if we wanted, because we simply don't have any "photo ids" from the government and have no interest in getting any.

I know about Bisq. It's the only decentralized "exchange" for Bitcoin-fiat that I know of. It has only a read-only API, meaning you cannot actually trade with it. The progress of their API seems to be zero since years and years when they started talking about it. I'm not holding my breath and believe that it could very well never be released.

For this reason, I ask you: Why is there no such thing as a decentralized Bitcoin API? Bisq apparently can stay around for manual use, so it can't be "illegal".

You'd think with all this money in circulation and all these countless marketplaces for cryptocurrencies, there would at least be one small project which give you the ability to script-trade Bitcoin! It's maddening to me that there is no such thing from the looks of it. I have searched for countless hours but nothing is found in search engines and nobody answers whenever I ask them on IRC or Stack sites.

Please at least give me a good reason why this is. Normally, there is at least some logical explanation for things. In this case, it's just utterly baffling to me.
I'd say that's just because nobody programmed it. Bisq community for example is short on programmers so they concentrate on the essentials. Companies have no interest in the development or shy away from the legal risk, where they are increasingly forced to perform financial police duties similar like banks (KYC/AML). Hopefully the Bisq DAO brings enough funds to have developers paid for this kind of work. 
Another concern is security. Successful replay or DOS attacks or any essential coding error might risk the whole Bisq project. Like with Bitcoin it's not easy to force the users to upgrade to latest version in case of malicious code.

Do you know the latest developments at the Bisq API? Have a look at this developer conference. There is as well a slack channel for the Bisq API interested.

Record of Bisq developers API discussion, Sept 2019