Skyrim was released in 2011. 4 years ago, and still lots and lots of players play it. Many games, even good games, when you stop playing them you move on. Skyrim, you leave it after some time playing other games, you come back.
It may not be your type of game, but saying "TES fun?" is just trolling.
He is not talking about the fun of the battle itself. He is saying that the reward should be more worth than the cost of the battle. And I think he is kind of right. Between the food to recover health, and the repairs, you spend more gold than you earn in any random encounter. And the xp you get is also very low. So, like he politely (more than you) explains, the problem is that it's more profitable to avoid random encounters, and while that would be accurate comparing to real life, this is a game, and searching for battles should be encouraged and rewarded.
Thanks for that great argument... oh wait, you are just repeating what he says that concerns him and tell him to suck it up, wihout any explanation on why you think that it works better this way.