Thank you, Burk! I'm your 50 claps, and I'd have given you 100 if I could have.
As a journalist I'm intimately familiar with U.S. copyright laws because if you've been on staff at big publications, as I have, you've usually had to sit through legal seminars on the issue (which I've also taught, briefly, as a journalism prof). And I see copyright violations on Medium often--for example, the full text of the lyrics to a rock song or a brief recent poem by a living poet whose works are obviously not in the public domain yet.
One reason why this matters so much is that copyright violations are, quite simply, stealing--in many cases, even IF you credit the photo (if you don't have permission to use it). You are taking what doesn't belong to you. And--with photos--you may be diminishing their value, or what the photographer could earn by selling them. Hope Medium responds promptly to you.