The new $350 Nintendo Switch OLED isn't any more durable than the base 2017 model, and you really should put a screen protector on it.
YouTuber Jerry Rig Everything answers a simple question: How much abuse can the Switch OLED withstand? Starting with the screen, the outer-most protective layer scratches very easily with a level 3 hardness gradient because the surface is made of plastic. This is an anti-scatter sheet that protects the glass OLED panel underneath--and also protects users from shards of glass should the screen shatter.
Overall the OLED model is structurally sound. It didn't break or crack under pressure and the bezels are made of metal. The YouTuber proceeds to torture the OLED model with 35-seconds of ignited lighter action, multiple scratches from a razor, and even some really rough bending. The Switch OLED bends and flexes a bit but it doesn't break in two.
"The Nintendo Switch OLED model is solid. Nintendo has upgraded the screen and the structure and I'm impressed," Jerry Rig Everything said.