Let’s first look at necessity of being a yogi.
If you want to participate in Olympics, training for it is necessary, and not optional. This holds true for anything, small to big. If you want a comfortable state of affairs in this body as well as when you leave this current body, then such knowledge is necessary, and not optional.
Coming to practicality of being a yogi, Krishna in Bhagavad Githa states an easy way to attain this state.