I usually play between 1-4 cash game tables depending on how focused on the game I feel I'll scale up and down through my session. Personally I like being able to see all my tables while I'm playing so I would have to go with tile. I think being able to see which villains are doing odd stuff gives you more of an advantage as opposed to just seeing HUD stats or not paying enough attention to have any information at all.
I think it's more important for tournament players to be able to fit massing amounts of tables on to their screen. From there I imagine they just go with what works best for them. For someone looking to play large amounts of MTTs per session long into the future a monitor with good resolution is going to be a pretty good investment as multi-tabling is how you're going to be able to maximize your hourly.
Alternatively if you're just starting out or not profitable or very profitable on a low table count there isn't a need to play more tables for the sake of more tables.
You should focus on what works best for your current game and your game going into the future.
Some of my friends who play MTTs have 12-15 tables up at once which melts my brain to even think about how they would do that.
Then again sometimes I degen and find myself 4-tabling zoom playing thousands of
hands in a session from the simplicity and ease of the 2x2 tile set up.
Think of what your poker goal is in 2 years and think of the set up you'll need to best reach that goal then work towards that. You don't need everything at once.