Because it is?Right, because it isn't very fun for you if you are going to have all of your abilities fail just because your DM got dumped by his girlfriend and he wants to lash out. The game was never about "whims" , I don't know why you keep wanting to insist on this as a difference.
Your example is a bad DM that forgot to tell you an important detail. That is an example of a bad DM.Doesn't it? "anything anywhere anytime might happen regardless of what the character does or does not do. And very often the character...and player..will never know the how or why of anything that happens or does not happen......ever."
I'm not talking about bad dms that make mistakes.The only difference between your description of old school play and my example... is the DM told me the what and why instead of just keeping quiet about the mistake.
This is an Old School New School difference. To be more of a "plus" said as: the DM gives you vast amounts of information, but you as a player must use your own skills and intelligence to use that information.......the DM gives you a chance not to die, ignoring any details or information.Yeah, instead of the DM trying to overwhelm you with information to obfuscate and cause you to make a deadly mistake... the DM gives you a chance to not die.
Well, there is another side. The improv game! At any time, the DM might decide to just make up any 'rules' they feel like to cover anything in the game.Gee, I wonder why that is when the other option is for the whims of the GM to lead to them causing harm or death to the player with no warning or reason. Why might people want to insist on sticking to the rules of the game, which are clearly laid out and available to everyone.