It's hard for most of us to imagine engaging in a project whose ultimate outcome we're unlikely ever to witness. Some of the projects that 'collapse-aware' folks might take on fall in this category. We might struggle in the next decades to minimize the impacts of climate change and try to avert various disasters; some bad things may nevertheless happen (some bad climate things seem likely to happen) within our lifetimes that won't be 'undone' or well adapted-to for generations.
One wonders, though, whether this 'near future' focus is a somewhat historically peculiar feature of our times. Today, the technological substrate upon which we rely and within which we live seems to change significantly across generations, and even within generations; but 200 years ago, the basic shape and feel of a life was likely much more stable across generations.
Many projects undertaken by people long ago were accomplished on a multi-generational scale. Cathedrals, aqueducts, and other large infrastructure are obvious examples; the multi-generational development of family farms, and the nomadic journeys of communities aware of their own historical trajectories, are more common and perhaps less-obvious examples.
Saying No to a Farm-Free Future
Review of Greer's Ecotechnic Future: https://www.resilience.org/stories/2009-11-19/review-ecotechnic-future-john-michael-greer/
Nichrome wire
Review of 3M 1860 https://www.youtube.com/watch?app=desktop&v=oEtuygo85ds
KN95 mask review https://www.youtube.com/watch?v=EpjqZTibcvg
Project idea -- start the Field School -- but, it's project-based (at least in part) -- it's a Field Research School
Biochar
Compressed air vehicles
... what else?