You have a point here, not sure what would be the best way to handle this?
On the one hand the sticky thread keeps things neat and organized here instead of having everyone post a photo, on the other hand as you said it is new threads that appear on your "subcribed" or "local" home feed, not new comments (unless you choose to), so photo comments in the megathread will have less visibility (except for those who specifically come to c/googlepixel, as they'll see a "(XX new)" in front of the comment count of the sticky thread if you use the web UI).
A weekly thread would probably have the best of both worlds but I'm not sure if we have enough activity to sustain weekly photography threads.
there's no one right answer but consider that Lemmy doesn't really get the volume of reddit so at least to start, there's less need to organize posts as much.
Doesn't get the same volume yet but as most third party Reddit apps are now moving to Lemmy that will start to change. I only came to Lemmy because of what used to be Sync for Reddit.