Green dots in videos and pictures

This link has examples from a large variety of phones and cameras that demonstrate lens flare, including some Samsungs, and also $10,000 and up professional cameras→iPhone Camera Lens Flare and Reflections - Apple Community

Lens flare is an artifact of having a light source either in the photo itself or slightly off to the side, but still striking the lens directly. All cameras with compound lenses (which means any camera that costs more than about $20) are susceptible to lens flare.

You are correct, its lens flare. No, there is no setting to eliminate them, this is a physical limitation of the lens.

Lens manufactures use coatings on the lens to reduce the flare. It's hard to see on a tiny lens on the phone but if you look at a regular size camera, you will notice a green or reddish tint to the lens. That is the coating. I think Apple reduced the coating on the lenses manufactured for the iPhone 13 as many people are reporting it to be worse on the 13's.

What is lens flare?

https://photographylife.com/what-is-ghosting-and-flare#:~:text=Lens%20flare%20occurs%20when%20a,being%20present%20in%20the%20image.