The typical experience reading a medium blog is that I can spend a minute, or a full 15 minutes, digesting the opening paragraphs. With the page idle that whole time. Then I can scroll down to a big brown smear, and read the whole caption before the associated image finishes loading.

I totally understand these images don't need to load with the first round of content. But you know I'm going to scroll down. Just use a timer or something.