I run some Minecraft servers and I do videos in them. Sometimes pixel art I see in the background as I do my videos are from things like Mario. Can I get in trouble copyright wise if let's say Nintendo were out to get me.
I would think that if Nintendo are out to get you you, then they probably could get you for copyright infringement. Most likely you would get a notice to remove the infringinging material rather than being sued immediately.
However most stuff like this is "under the radar" of such companies.