"Too seriously" is subjective.
Some people find entertainment in finding the best gear combinations and rotations, knowing the mechanics in details, reach the top of the leaderboards and play as good as one possibly can. Which in turn kind of implies that they take it seriously, but that's their way of having fun.

I take the game very casually, but ...
- I get annoyed when people don't even try to coordinate each other in group play such as a trial. Coordination and playing together is part of the fun, and it's not fun when noone really cares
- I get annoyed when people in TeamSpeak start to monopolize the conversation with real life stuff such as their mother in law having the flu. I mean, I emphatize and all, but that's not what I come to Tamriel for, really.
- I get annoyed when people feel entitled to ask me for Kuta, alloys, columbines, whatever it is they need, because they did not take the time to farm or keep stuff or manage their inventory. And of course they have no gold either.

The line between fun and serious is very thin and fun can destroy "serious" just as much as serious can destroy funny. It's part of a guild's culture to set that line (at a different level for each guild, obviously). That's why guilds are so useful. It brings like-minded people together.

ViciousVamps1 wrote: »

Thats how to play im talking about players that get angry and scream and cry because i beat them in a duel

That's, in my humble opinion, not "taking the game (too) seriously" but "putting (too) much ego into the game". Which are different things (although, admittedly, related).

The problem is that the game's design is fairly aggressive (realistic ?). Even if you don't take things seriously, you like to win and you hate to lose, you hate being sent 5 meters backwards by your opponent's greatsword, CCs are infuriating, etc... the game is designed to trigger strong emotions during the fight (positive if you win, negative if you lose).