What I personally always think when it comes to the future is that we as humans are bad at predicting how hard a certain imagined technology actually is to realise. For example at the beginning of the century we could easily image wireless headphones and smart watches, but nobody expected them to be accessories to a portable phone because we didn't know these two technologies would match into one (wireless phone calls and small computers were definitely two different things back then). Another example is flying cars, and more recently self-driving cars. Developing software for this turned out way harder then expected, while 'self-thinking machines' are much easier. I always think of this scene in I, Robot where the robot draws an image, back then this seemed much harder than a computer which arms and legs. In practice both have become possible over the last 20 years, but while generative AI is available to everyone, robots are only available to agencies that can also afford warships and fighter jets.
My main point it is extremely hard to predict where we will be in 100 years, but it might help to do this in a few steps. Not saying you have to publish those steps, but if you're gonna use AI anyway you could try and set up a bunch of agents that work together:
Agent 1: analyse the past, let agent 2 know about how this tech came to be A2: based on this, imagine where this tech will be in 10 years, let agent 3 know your prediction A3: analyse the financial part of this development, tell A4 A4 - based on this, explore possibilities in 25 years, tell a5 A5 - analyse these possibilities, tell what is likely and what is not A6 - extrapolate the likely path to the following 25 years A7 - analyse if the likelihood of this 50 year prediction Etc etc
By setting up agents with different point of views you might have a better chance of avoiding the blind spots a single ai will have (since it doesn't have knowledge itself, it just puts words together)
Also I'd make the difference between technological advancement (flying cars) and societal developments (equal rights), since these progressions don't behave in the same way.