Those are interesting questions.

What would you save? Given that all of our technology is completely dependent upon fossil fuels, which are finite, are you maybe falsely assuming that in the future there will be a comparable energy source emerge that will work with our now technology? Or,.are we destined to return to being small bands of hunter/gatherers who have no use for technological advancements of today?

Assuming there are people selectes as preservationists of tech utopia, how can you ensure they will make it through the bottleneck? Viruses and natural disasters don't care what you devoted your life to. The folks in St Petersburg who tried to preserve seeds and knowledge during a time of famine were eventually eaten by those they thought were an acceptable sacrifice to preserve knowledge for some unknown tomorrow.

But even if you did manage that, they're going to have to educate children in the future to understand the knowledge or leave some sort of repository or library. Or both. But by the time people get to a development point of being able to use it, the language will have changed significantly.

I think people are preparing and trying to save some things. But it's piecemeal and personal. I think it's mostly looking backward too. Not high tech, but passive principles. Basic science. Focused on survival. That kind of thing. They're reacquiring lost skills like blacksmithing, textiles, farming, animal husbandry, herbology, etc.

Ultimately, a lot of that will be lost as well most likely, but it's presence in the population may help save more lives once the energy goes.