Chess and Go are not solved games, and will likely not be for some time (10+ years, for Go at least). Solving non-deterministic problems are even harder, and many likely will not be accomplished within our lifetimes[1].
There is no AI system that can generally make more accurate diagnoses than a physician. We're not there quite yet, and it will be a while. The best we've come are some pretty advanced expert systems, but these require very heavy input from physicians[2]. Please provide sources to validate your claims on the progress of AI. Extrapolation from data is dangerous, extrapolation from falsity is ignorance.
As far as your take on understanding goes, the human "meaning" of things is inherently subjective. If we define "meaning" as some thing's value or role based on environmental context, then just like humans, any artificially intelligent system will only be able to determine meaning based on observations of the environment and both individual and collective experience.
It's interesting that you seem to be focusing primarily on social domains that have inherently "human" contexts. Beyond misunderstanding the point of this paper, and the way AI systems work, I think you're missing the point. AI is, and for the time being will remain, an extension of the human mind. The decision-making needs to be developed (at some core level) by a human. Those goals need to be set by a human. The experiences and observational capabilities ultimately need to be determined by a human. Even AI systems that build other AI systems need to be directed to do so, and with strict goals, set by a human [3].
I highly suggest you take a moment to read openai's mission statement: https://openai.com/about/. AI is a tool. And like any powerful tool it must be used responsibly, freely, and openly. Openai is pursuing this goal and making efforts to ensure that this tool is available to as many people as possible to avoid the abuses implicit to your concerns.
You obviously have an interest in AI and some knowledge of the field, but I worry your comments veer a bit towards fear-mongering. I suggest you use openai and resources like it to enrich your knowledge of both the advances and concerns of AI, because those are important, and we definitely need people thinking about these things.
Ultimately, you are absolutely correct that eventually these systems will probably have the technical capability to influence elections, the economy, and more. But the only way they will is under the direction of humans. It it not the machine you should fear, but the man behind it. The same thing you ought to have been fearing all along.
1. http://fragrieu.free.fr/SearchingForSolutions.pdf 2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1307157/ 3. https://arxiv.org/abs/1611.02779