I feel like many other people take it seriously. I try to build a good team and have a good battle but most of the players I come across are seriously over prepared with Pokemon strictly from the Uber/OU tiers and always use choice items. It annoys me that I have to conform to everyone elses way of battling coz if I try use my own strategy it's not even going to compare to the pre-built teams that you can just look up on the internet. Sure, I suppose it's the 'best' way to win but it makes for little personal customization - you're basically forced to do what everyone else is doing if you want to win or even last in battle. So to answer your question I try not to take it too seriously because I know that there's always gonna be people out there who know more and are more prepared and I'm very likely to lose. I don't own any choice items I would rather battle against friends over IR who are like me and prefer building their own unique teams and strategy.