I have contemplated and sketched out what would be required to build a slot loading sd card reader. Ultimately, I believe a vertical mount door loading mechanism* is cheaper, more reliable, and certainly has a decent aesthetic.
Sony did release drives, DGR looks at one in this video for example https://www.youtube.com/watch?v=CzwtCBj5jEs . It's yet another example in the weird graveyard of replacements for the 1.44MB floppy that didn't catch on.
Since I am also an avid DSLR photographer, the first decision I made was to use Adobe Lightroom (Classic) as the "single source of truth" to manage all our photos.
This means obviously importing all photos taken via my DSLR into Lightroom, but also syncing all photos taken on our iPhones via the Lightroom Mobile App.
Lightroom Classic keeps all the (compressed) photos in the Adobe cloud for easy sharing and browsing, but also writes them out (unaltered) to a directory on my Local NAS.
This NAS gets automatically backed up via Arq Backup (https://www.arqbackup.com) to an encrypted Amazon S3 bucket. Additionally, once or twice a year I create a versioned copy of the NAS via Carbon Copy Cloner (https://bombich.com/) to an external hard drive. This hard drive is stored offsite somewhere safe.
In a nutshell, for around $12 a month + a NAS + a hard drive, we have all the convenience of the Adobe Lightroom cloud combined with a local copy on the NAS, a cloud copy on S3 (in case Lightroom cloud gets corrupted) and an offsite copy (in case our place and the whole internet burns down :-)).
eBay, reddit, Netflix. But at reddit it was just the four of us and at Netflix we didn't really have product managers except in the UI area, but those folks were all super talented.
https://www.amazon.de/Show-Stopper-Cloth-BREAKNECK-GENERATIO...