Overglossy and reflective

Everything has worked with reflections for me, and everthing looked great, until one point where I think I created a new special light
(but deleted it afterwards). From all of a sudden without me changing any settings in the materials, everything looked like this:

It’s incredibly reflective and shiny out of no reason. I deleted every single light I had in my project, even the sky sphere (I readded that though)
and still nothing has changed. Is there any hidden setting someone knows that would help me with this? :o

Are you using FXAA instead of temporal AA by any chance?

Did you rebuild the lighting after deleting the problematic light? I ran into an issue similar to this in the past, and it was caused by a light source somehow finding itself beneath my floor. You should check for that as well.

What is a “new special light?”
Also play it in a standalone game to troubleshoot editor settings. It looks like a combo of a really low roughness value, a dynamic light, and no antialiasing.