I recently spent a lot of time considering how to do my own storage and backups for a collection of mkv files I have. Your solution depends on how frequently you need to access the data, how frequently you need to modify the data and how frequently you need to add data to the archive.
For family photos, you might view them once every couple years, just to browse randomly. Every once in a while you might access the data with the intention of finding a specific photo. The data is of course never modified and only expanded once every five years or so.
So, low bandwidth, infrequent access and expansion and no modification. The winner by a mile is Blu-ray.
A hdd will de-magnetize over a very short period of time even if it’s stored in ideal condition. Less than a decade. You need to plug it in and let it refresh those tracks. If you keep it plugged in all the time then something else will die. Any way you slice it, there will be maintenance.
The data on a Blu-ray just sits there. It will outlast you.
Some Blu-ray Discs can have problems. This is because of improper materials and poor manufacturing. If the layers of plastic that sandwich the medium become delaminated or damaged in some way, this will lead to the oxidation of the data medium and loss of data. A properly manufactured disc like a Sony archival disc will never do that. And they make discs with data mediums that don’t oxidize so those ones can hypothetically last for thousands of years. Despite what people might say, a proper Blu-ray Disc is a great way to store data.
So here’s the deal. Get rid of duplicate pictures and pictures you don’t really care for. Compress as tightly as you can. Burn a copy of those files to a set of discs. Then another set of discs from another brand. And then another and continue however many times makes sense for your budget/ value of the data. Send each set to a different family member starting with the most remote. When it time to update the database, send out the latest discs.