I think it's going to be a very boring game. They are surely going to park a bus. No way you can score 4+ against a bus, no team would be able to do that. I'm not sure if motivation will even be a factor, a professional team that parks a bus is extremely discouraging even for a team like Barca.
Now, if they don't park a bus (which I highly doubt), then yes I believe we can score 4+. However, that'll put Unai's job at risk.
I don't really mind exiting CL early. It'll give more rest for La Liga, which we can surely knick from RM. If RM's form also continues, then I don't see them getting past the other CL giants. A double 3 seasons in a row is amazing, even for a team like Barca. Lucho would go down as a historical Barca coach and end on a high.