Mmm, kind of? 2 stroke has its place though. It's reliable, cheap to build and easy to maintain vs 4 stroke. Which makes it perfect for simple engines like lawn mowers and yard trimmers.

Gas-gas refrigeration doesn't really have any advantages over liquid-gas. So we don't really use it since perfecting the gas-liquid version. They used to use air refrigeration cycles. But not really anymore because it's so bulky due to the sheer amount of space/gas needed.