One and a half decades after the bleak outlook at the beginning of the 2020s, it is becoming increasingly clear that the worst effects of the climate crisis can either be avoided or at least be mitigated. The world has changed a lot in the time between 2020 and 2035 - and mostly for the better. How has the world been changed and what does it look like now?
(This is admittedly an unusual application of the AskHN format. It is deliberately vague, has no clear answers and is mostly intended to inspire people to imagine a positive future. If you find it inappropriate, flag it - I'll get the message)
Autonomous bus and taxi services led to less casualties on the streets because less people are still driving themselves (less DUI, being distracted, tired or otherwise not fit to drive).
Taxi services got a lot cheaper because there are no longer drivers who need to be paid which in turn accelerated the transition away from car ownership.
Traffic flow also improved because having a small fraction of autonomous vehicles on the road already prevents traffic jams out of nowhere by cushioning the density waves that can appear in traffic by human drivers (that's really a thing!).
Overall look of cities improved since less parking spots are required. Rules that regulated required parking spaces for customers were lifted which gave the opportunity to open more shops in closer proximity.
I will add it later if I can think of more.
Because this energy source only requires access to the sky, poor nations were able to develop their own renewable power grids. Economies based upon the sale of oil are reforming to be based more upon the output of their workers, reducing the power of the elites and making for more equitable societies. The change in the balance of power has created new fault lines in international diplomacy, but because these changes did not require force, the changes have been largely peaceful.
Bloomberg gets humiliated in the 2020 election, he really comes to understand Mancur Olson and realizes that for what he spent on his failed presidential bid he could seed the ocean with iron oxide to capture a significant amount of carbon. Some people complain about it, but because the U.S. is not a signatory to the U.N. law of the sea, nobody can stop him.
In 2022 a group of people based in Miami do a kickstarter to buy a used A330 and modify it to spray sulfur dioxide into the stratosphere.
Elon Musk gets his "Starship" working by 2024 and a consortium of several governments and private industry start a moonbase to produce oxygen and iron on the moon, then to move an asteroid to the Sun-Earth L1 point and fabricate a sunshade which deflects enough sunlight to reliably cool the earth by 2035.
The nuclear non-proliferation treaty is scrapped by 2028 after violations by North Korea, Iran, Brazil, South Korea, Japan and other countries. Thus the political barriers to nuclear fuel recycling are eliminated. By 2035 we are seeing the first demonstration-scale dry nuclear power plants that use gas turbines and higher temperatures to greatly reduce capital costs. There is a fierce competition between fast breeder (sodium cooled), molten salt, and high-temperature graphite reactors with prismatic fuel. It isn't until 2045 that this starts to have a major impact, however.