I don't think You or anyone have to explain anything about a photo. It is not an obligation. They can speak itself but I think there's a reason why a creator is taking that object, which is something often highlighted in art or photography exhibition. Again, I am not saying you have to say verbose description.

Another point I want to raise is the market where we put our content. Steem as blockchain is diverse. There are people who like short content, blog posts, articles, essays, photography, even gaming. And I am sure people do a great job on finding their own community and support each other. I always see it as, if I want to attract certain types of readers then I must do what attract them. I will not get someone attention if they're not interested in my content. Regarding what you mentioned ,

Steem whales don't look with good eyes on microblogging creators.

It might be or might not be true. It seems to me that they prefer medium to long blog posts. But that's not often the case. I think there are some whales out there who will upvote microblogging contents. Nonetheless, instead of thinking they are whales, think that they're also our readers. Perhaps when "whales" don't come our way, it might means- it's outside their interests.

From my experience writing a medium-long content, it's time consuming. It's even more disheartening when you get less interaction for something informative. I do a lot of stream of consciousness writing as well or just rambling. Interestingly, my rambling gets more engagement than my informative content.