I’ll go for the 14 tbh

I use my phone for social media too. I upgraded from the 12 pro max to the 14 and omg it’s amazing! The photos look so much better than they did on my 12. Maybe it will please you better than the 15.

I had my s21 plus back in 2021 and switched to iPhone 13 Pro Max on 2022. My battery on the s21 was lasting only 2 to 3 hours.

You clicked probably the option to delete those photos from your gallery to save up space since you already had them on google photos.