How optimistic can we be?

[miniboes]

I find myself growing increasingly pessimistic about our future. The sustainability debate is dominated by two wrong sides (antinuclear and deniars/slackers), leading to incremental progress. We throw around antibiotics carelessly (particularly in animal agriculture), increasing immunity risk. AI research is rushing forward without ensuring safety first. Meanwhile, it seems politicians and media outlets are primarily concerned with sensational, short term issues.

There are movements present that seek to counteract all of these trends, but I strongly doubt they will succeed in time to help much. Am I wrong to be pessimistic? How likely do you think it is we can counteract these problems before they have disastrous impacts (including existential risk)?

[brimstoneSalad]

Well, I hope I can put a couple of your fears to rest.

AI research is rushing forward without ensuring safety first.

There are computational limits on the quantum scale, speed limits on information transmission, as well as thermodynamic limits that prohibit the god-like super-intelligence people often fear.
Human beings would have to allocate absurd amounts of processing power to something deliberately to make it smarter than a person, and even then we would expect diminishing returns. I covered a little bit of this stuff when debunking the idea of a simulated universe in other threads.
This limit can be partially overcome by distributed computing by way of viruses, but not only have our defenses become pretty good from virus attacks created by humans, but worst case we would be dealing with a very large but slow brain because many solutions can't be easily distributed like that.

Anyway, the others are legitimate concerns, but probably not total existential risks.

The sustainability debate is dominated by two wrong sides (antinuclear and deniars/slackers), leading to incremental progress.

This really sucks. A lot of cities will probably flood, and billions of people are likely to die of famine in the developing world. War may also break out. It's going to be really terrible if we can't switch over to nuclear power and sustainable energy.
For people in the developed world and not living anywhere the ocean is going to be soon, food and energy prices will probably go up and there may be serious economic issues, but your life probably won't be at risk unless war comes to your back door. It's just going to be a few shitty decades. Although healthcare may be more difficult to come by, and you could die from something else.

There is a chance to fix this, but we have to change public opinion on nuclear power and GMO (particularly the low methane rice) and curtail animal agriculture, then start capturing carbon aggressively and achieve a negative carbon impact.

We throw around antibiotics carelessly (particularly in animal agriculture), increasing immunity risk.

This is pretty scary. Your best bet is avoiding contact with antibiotics if you don't really need them, and avoiding those products, and staying out of hospitals if you can and away from farms raising animals or using manure where resistant strains may be.
Use antiseptics, to which these bacteria cannot become resistant. Use antibiotic free hand sanitizer if you touch something in public, and make sure your soaps are antibiotic free.

A lot of people will probably start dying of post operative infections. Things like heart bypasses are going to become a lot more dangerous, and could become death sentences for many. The best bet is to stay out of the hospital if you can, and if you go to the doctor's office, be very careful not to touch anything.

Our immune systems are pretty good at dealing with the bacteria themselves, even the antibiotic resistant ones, it's just in cases of accidents and surgeries where we're at the highest risk.

Bacteria has for a long time lost its aura of terror, and viruses have been the main bogeyman of the past decades, but that's going to change.
Thankfully bacteria are very easy to control with proper hygiene, being so large that they aren't typically as airborne (and easier to filter out). There are some scary exceptions, though, with coughing/sneezing aerosols. https://en.wikipedia.org/wiki/Pneumonic_plague Many bacterial disease can travel short distances in air.

I don't see any more an existential risk from bacteria now than it was before antibiotics. Massive death toll, particularly in developing countries, for people with weak immune systems, and those who need surgery... but not an existential risk for humanity.