Most RPGs I have played have mechincs for things like surprise whereby if you are unaware of an attack you suffer penalties and/or your attacker gains advantages.  One of those might be that you lose your ability to dodge.  They also usually define if/when certain abilities can or cannot be used.  Ultimately it doesn’t really make any difference as long as the rules are all internally consistent – you can always make a case both for an against an action being usable in any given context.  I don’t see any reason why dodge cannot be used at point blank range, at that range you are virtually in melee combat anyway however you would also expect there to be some additional bonuses to the attacker at point blank that would actually make dodging more difficult.  I am not saying that there are no bad games mechanics out there, maybe in some games the dodge mechanic isn’t particularly good, but in and of themselves they don’t represent a case for RPGs in general needing to learn from wargames, they’re just an example of a bad rule.  Pretty sure if you look at any wargame you will also find some rules that don’t seem to make any sense.  Personally I think the family of D20 system derivative games (D&D, Pathfinder etc) has built its entire reputation and silly mechanics, things that have been wrong with the game since its inception, but people still love it and ultimately it still works as a game

I would also argue that in an RPG all sides should not always play by the same rules.  The GM is responsible for what happens regardless of the dice rolls and there’s some very good reasons why, as a GM, you might actually play by the rules and might want to bend them or fudge them, especially if you realise that you have either over or under estimated the players abilities or they’re just having a bad day with the dice.  The GM’s job is not to make a fair fight but to tell an interesting story and what goes on behind the GM’s screen stays behind the GM’s screen.

In some games the GM and the players don’t play by the same rules at all – in Symbaroum for example the GM makes no dice rolls at all, every action is driven entirely by the players.  When the baddies attack a player, they roll defence with modifiers based on the the attackers’ abilities.