There may be phones that are, on paper, more powerful than the Switch, but phone games typically have to support a wide range of different models and so aren't as specifically optimized for the hardware as games made for the Switch.

As a result, Switch punches above its weight, with games like FAST RMX and Outlast II exceeding what you'd expect from a phone of equivalent spec. Heck, I'm no technical expert but I think I have yet to see any smartphone title outshine the visuals of those games.

Now let's compare to a $300 phone.. should be good

Let's also compare libraries... should be good. 

I will say for the person that mentioned the lowest resolution om the switch version, since the last update the Switch version suffers far less frame drops and looks much much much better and it's immediately noticeable. I doubt it even hits 360p on portable mode now:

We’re comparing a phone to a dedicated gaming device now?

Phones have been close in power to dedicated gaming devices for nearly a decade now.

Which phones specificaly?

Countless models. In 2010 you could get a Samsung Galaxy S with better specs than last gen handhelds of the time. Phones with better specs than the Vita started releasing quite early in that system's life, like the Nexus 4 in 2012.

Yes.. lets ;)

I should note since the last fornite update, epic specified in the patch notes that they increased the dynamic resolution on Switch, which might have some effect here. Switch version definitely seems to have been helped by better optimisation and very good native unreal engine support considering Nintendo was looking that engine to run on Switch from the start, even using it for their own games such as Yoshi.

"Significant GPU optimization on Switch. Moved to the high-end forward renderer. This increases dynamic resolution by 10% in expensive scenes."

https://nintendoeverything.com/fortnite-version-5-20-patch-notes/