Yes, this is the line of code for the photo in question:
<img src="images/Mobile-Builder-Screen-2.png" loading="lazy" width="640" sizes="(max-width: 479px) 100vw, (max-width: 767px) 85vw, (max-width: 991px) 48vw, 50vw" srcset="images/Mobile-Builder-Screen-2-p-500.png 500w, images/Mobile-Builder-Screen-2-p-800.png 800w, images/Mobile-Builder-Screen-2-p-1080.png 1080w, images/Mobile-Builder-Screen-2.png 1280w" alt="">
The code says that there should be a photo that is 500px wide, but it does not seem to be loading that photo, instead loading the 1080px wide photo.
In checking the /images folder, Webflow indeed does generate to 500px wide version, it just does not load on mobile.
Edit: there are other photos which this bug affects as well, above is just 1 example