Pragmatism and realism is important.
Some weirdo RAW format? Will probably suck to deal with. Already sucks to deal with. Don’t expect it to last long and maybe keep the JPGs around for your grandkids or rather grand-grand-grand-grandkids.
JPG? I’m quite willing to bet that, baring the apocalypse, this format will be easy to read in 100, 500 or 1000 years. I’m really that certain about it. I’m even certain that in 100 or 500 years whatever OS on whatever device will come with out of the box support for JPGs. Maybe you will need an afternoon of digging to get JPGs displayed in 1000 years … but that should be about it.
Ok, ok, those predictions are quite absurd, but I really would be wary of underestimating the existing and continuing ubiquity of the JPG format. There are probably billions of JPGs created every day, even if you limit it just to JPGs that result from light hitting some sort of image sensor. And that will continue for at least a couple decades. In the end a, what, maybe 80 to 100 year active lifetime of the format (remember, we are already at a quarter century) might seem short in the grand scheme of things, but the cost of just keeping support around will be so low … (again, barring the apocalypse)
My OS can open some weird-ass image formats right out of the box. I can None of those formats (no other image format, period) has ever been as popular or as widespread as JPG … by a wide, wide margin. JPG is gonna be ok. If nothing else.
So I wouldn’t worry about the format. I would worry about what you use to store those images and how you will hand it down. (Often analog photos are on some attic or similar place somewhere, often long forgotten even by the person who took them. Then someone stumbles across them and that is beautiful. Not so easy to recreate with digital images. How do you stumble across that? How do you just keep it around somewhere safely)
You are certainly right that film negatives or positives are more likely to survive the literal apocalypse (where we lose all knowledge about using computers), but I’m not so sure about them being more likely to survive into the deep future … (Though in some ways you do have a point: I think in some ways it’s more likely that your grandkids will stumble across and know how to deal with your box of negatives in the attic than, I don’t know, your old hard drive? Your old PC? How do you even keep such stuff around?)
But my point is this: JPGs are easy. Move beyond that and it gets hard. Any kind of interactive content is a nightmare.