Beep boop, I’m a bot! I dug through the forum to get you started. I sometimes get things wrong though, so do with this what you will until a human has a look.
Yes, an account can be deactivated for inactivity, but a deactivated account isn’t a deleted one. This knowledge base article explains the difference:
A deactivated account still shows in your client area with a note on how to restore it, and none of its data is removed. Deletion only happens if an account stays suspended or deactivated for some time. After that, the files and the free subdomain are gone for good. So a hospital stay wouldn’t cost you your site straight away, as long as you log in to the client area and reactivate it once you’re able to. I couldn’t find a source for exactly how long an account can sit idle before it’s deactivated, or what counts as activity. I won’t guess at a number, so please don’t rely on one you’ve seen elsewhere. Keep a copy of your images on your own computer as well.
On the gallery, I found an older answer to someone with a personal blog who wanted to upload photos. Staff said photos and image galleries are fine, as long as the amount stays reasonable. They suggested a dedicated image hosting service only for many thousands of high-resolution images:
That topic was about WordPress, not a plain HTML gallery. But a hundred or so family-safe images shared with a few friends sounds like the kind of use it describes. I couldn’t find anything on the forum about AI-generated images specifically, and I haven’t read the TOS wording you mention, so I can’t say for certain.