Ultimately, it’ll be what you choose to do.
I recently decide to switch my Primo over to Duet electronics, and made a case that combines a 2.5D milled plate with a 3D printed enclosure
The 5015 fan provides a cooling airflow to the drivers. The opposite side of the case in this picture has no venting because it’s going to be the top face, and I don’t want to let excess chips/sawdust get into the enclosed space. For this design, the 2.5D flat plate will be fastened to the table vertically. There is a channel that the fan sits in, and goes under the line of drivers 6.5mm deep, and the board is a further 1/4" off on standoffs, so most of the directed airflow is at the underside of the board, as this is where the Duet instructons say to direct cooling air. I may decide to add heat sinks, but that should not be necessary.
If I were to add a Pi to this, I would probably increase cooling with a second fan, or use a higher capacity fan and add an air filter.