No. I judge players based on what I see on game day. But to your question the quality of slot weapons and #2 wideouts is relatively similar. Some teams one is tougher than the other, but the big thing to remember is that slot weapons typically aren't deep threats, they're usually good at quick separation due to routes or agility, or sometimes bring size/physicality but aren't capable of making their money outside the hashes.
In other words it's apples and oranges to a certain extent. NRC isn't an outside the hashes CB. And I'll add that slot corners are very easy to find vs guys who can survive outside. Back to NRC vs Hill, I would summarize it as NRC is a very good slot corner and Hill is a subpar CB2.
And btw all this is why PFF grades need to be taken with a grain of salt.