There are two hard parts: security and discoverability. As a programmer I know 95% of what is needed already exists, what is left is security and some ease of use.

plex (https://www.plex.tv/) already has most of what you need. However if I put a video of my kid's first words on plex how does grandma find it?

I would love to see it, too. The good news is that these are all solved problems. It's more about tailoring the information and distributing it. It could be the online equivalent of a Sears article on how to build a shed.

I personally really enjoyed the "Links" sections at the bottoms of everyone's Web 1.0 pages.