how much further could they or it possibly go beyond what humans have programmed?

What do you expect from this?

we ourselves could be AI created by aliens many thousands of years ago or however long...

It would be irrelevant, basically, just as the question of creation in general is less relevant than one might commonly think. Life without a creation ethos, on the other hand, is quite possible and also enjoyable. You work with what you have and know - which is a lot :)

put out there by the people in power in order to lead the masses down a certain way of thinking?

I would say that the masses can be controlled quite wonderfully even without AI. Media, films, stories, ideologies, the internet etc. do their part and influence thoughts, feelings and future prognoses of a dystopian and utopian nature.
Humans have been thinking about themselves since they became self-aware. One can achieve too much of a good thing with it, as always there are more than two sides to every thing.

But since we are also carnal beings, we learn to speak, to walk, through our flesh, that is, our organic existence, through the body languages of those around us. The body remembers falls, sprained limbs, falling off a bike, running into a wall, the feeling in the stomach when you laugh heartily and the thick lump in the throat when you cry. We are organic through and through, or, if you want to put it more poetically, we are made of the earthly elements mixed with a little stardust in our blood, so that we too are electromagnetic.

Yes, we will see, as always ;)

I just blogged something after months of not being very active here. Come and visit me.