So multiple users use multiple devices to access the same large photo collection? And cloud storage can be an expensive money drain over time.
What I'm about to describe is an option that may be more hassle than you want to get into, but then again, it might be worthwhile.
NAS - network attached storage. I don't have one myself. Here's a basic concept. Imagine what looks like a really big external drive with 2 or 4 drive bays to hold hard drives or SSDs, and by having more than one, it can copy the data so you've got automatic backup done. Cool, but not a great trick. Now imagine this thing is really a computer itself with its own operating system (granted, no monitor so you won't be using it like a computer), so you can install ap.s and get it to do various things. Okay, so it sounds like it's got optional gimmicks, but big deal, you want multiple people with multiple devices to access your photo collection. It's be nice if that didn't involve paying into perpetuity for cloud photo storage.
Well, that NAS can store your entire photo library (even if it is huge) and act as a server to deliver it to any of your devices. You can even set it up to do this over the Internet, IIRC, so it serves as a big disc drive/server (and maybe backup system for at least some of those devices) over wifi (and/or ethernet) for your household and also allows online access from abroad.
Synology seems to be the dominant brand I see in reviews.
If a NAS sounds to you like more drama than decent users need, cool. I just want to make sure you are aware that option exists.