I use iCloud for my photos and they are shared on both my phone and computer automatically. I'm not understanding what the question is perhaps in this thread - it seems easy and automated to me.
Correction - I never put photos here and perhaps that is the question. Because as I look around I see no easy way to do that.
This discussion board is built with old code though, right? I have no problems putting my photos anywhere else - FB, Twitter, Instagram, slack, etc. It seems to me that this forum is just older technology ...