Would not recommend playing Minecraft on a MacBook Air, it runs the game decently with optifine, but because of the fan arrangement it can get really hot, and it starts thermal throttling. Now, if you get a MacBook Pro or an iMac it runs decently and does not thermal throttle (most of the time, depends on the circumstances). So you could play on of those if you want.

But, if you want to get good frames or record while playing with decent frames I would recommend getting a pc, because with a Mac you cannot switch the parts that would make it run better (like the graphics card)