Pinker actually addressed this, but unfortunately I can't remember in which book/lecture/talk/article. Largely paraphrasing he said that we have to work for the gains, but that doesn't mean we can't have a positive attitude about these processes. (Such as comparative advantage resulting in trade resulting in cooperation and some degree of altruism - or we can just call it "counterparty risk management", or simply looking out for your buyers and suppliers.)
Current institutions as a vague continuity or the same?
Because if Pinker and other try to argue that current institutions have been historically enough, we just continue growth, they are very much wrong.
Benefits from innovations and growth have been accompanied with massive institutional changes in every 30 years or so. The current era is becoming an exception where institutions are becoming stale after 40-50 years of the same. That threatens continuity because institutions have to change in response to the change in the environment or they collapse.
Yes, you can.
We are learning and adapting our civilizations, and by most measures, it looks like we are 'getting better'.
If we continue along this path, things will likely improve.
Nobody is suggesting that there cannot be alternate dynamics. We all face the risk of war, famine, climate change etc.
You can't extrapolation the future from current trends. There are discontinuities and challenges that can change the dynamics.