Can someone here explain the appeal of "competitive" pokemon?

It's not skill based at all, it's just rock paper scissors with RNG thrown in. Or to be more specific, buff (stat increases, weather, rapid spin/spikes) attack switch. It's just a triangle. Attack beats buff, buff beats switch, switch beats attack. I know theres stuff that makes it a bit more complex than this, but this is in 90% of the cases what decides the game. It's just switching until someone gets a favourable match up and uses shell smash or quiver dance and wins. All the teams have interchangeable pokemon doing similar things and the general strategy is very unvaried (there are different ways to do the exact same thing, but a skarmory with whirlwind is the same as a garchomp with dragon tail). Add in misses, crits, rng based status', and you have a very luck based thing.

I can't for the life of me understand why you would want to put the time in grinding and breeding a decent team to play rock paper scissors with RNG.