"That part made sense and was adjusted already."

No, it wasn't adjusted already. I fixed it. - see the history: https://www.openstreetmap.org/way/440431477/history

If the sand is not all clear and open, it's probably not a beach, it's just sandy substrate covered in grass and scrub along a river bank. The definition of a beach is pretty clear. The imagery here is good enough to identify individual plants and clearly see the border of the actual beach area.