Until it doesn't. Or rather when Google no longer benefits from photos as a training corpus it will no longer have a business rationale for keeping old photos.

While 43,000 photos sounds like a lot and would have substantial heft as physical prints even at 4x6. As digital files they will fit on a $60 external spinning disk with room to spare. Even as RAW files.

But to me, a single print of a child's soccer game is going to have more impact than a thousand digital snapshots. Please, for the sake of the people you want to see your pictures, make some prints and put them in frames and hang them on a wall. They will last. Because physics hasn't changed. Good luck.

But the amazingness of Google's Photo service is the search.

My wife and I reminisce and say something like "remember that time we went to a Yankees/Red Sox baseball game - so much fun". I search for "Yankees baseball", and boom, there's the photo of my wife, at the stadium, from 2012.

I can't replicate that functionality.

Also, I ruthlessly prune my photo collection, because once I clear out all the cruft that I don't care about (photos that are blurry, near duplicate, no longer relevant, etc), I have half as many photos to look through. I only keep 500-1000 photos per year, one folder per year, as well as a synced Camera Roll folder with not-yet-processed photos.

Not only does this make browsing through my photo collection a much more enjoyable experience, it doesn't take up much space. I have my entire photo collection (11000 photos from the last 12 years) stored locally on my phone in full resolution, as well as backed up in various other locations.

While you still have your originals from all those laptops and phones and drives, copy your originals onto storage that you own. If you have a mess of duplicates like I did, you're free to use PhotoStructure to dedup and sweep everything into one neat pile on one big drive. It's free during the beta in exchange for your feedback. https://photostructure.com/about/introducing-photostructure/

Eventually an unbounded archive grows so large & onerous you'll never really want to look through it again.

(This was one good feature of prints & albums. A minimum level of curation was required)

I've done the same as you, importing every family digital photo I can find into iCloud Photos. Flip Phones, Palm, BlackBerry, early digital cameras. $10 data cables from eBay are the way to go.

I've yet to tackle the film photos and slides, but that's next on the list.

The descriptions exported as "Copy of... #{description}" which is really lame. And cumbersome to clean up.

And then there were a whole host of videos and photos that did not import with the original date/time stamp.

I run a docker image on one of my local servers that does a sync of anything new in Google Photos each time it is run. Gives me added peace of mind.