Generally speaking,yeah,there is difference between the weapons. In reallity tho it didn't really mattered,most of the noble's kids were pretty proficient with those weapons at early age. They train by actual fighting for most of their early life,so by the age of 10 they were pretty good warriors. After all at the age of 13 most boys were seen as man already. The difficulty in training is more of modern thing when people do it as hobby where you get 3 hours a week doing it. Back then it was more about reading the battle than knowing how to slash or stab,that shit was more a muscle memory than anything.
Sure, you could say that they all had martial weapon proficiency and could pick up any weapon and fight with it. I still say there are weapons that take less time to learn to use competently, but practically speaking if it was your job to fight yes you'd have time to become competent with pretty much all of them. Oviously there were better fighters and worse fighters, and individuals were better or worse with specific weapons, but beyond that I agree with you on "muh studied the blade" shit being dumb.
They were used more out of economical reason than because they were easier to use. It was a lot more cheaper and faster to make stick with an iron point than a well balanced sword. Also the peasants were kind off proficient with using such weapons in their daily life in the form of pitchforks and such. Same shit with axes and hammers,they were practical tools that could be used as weapons and the peasants were used to handle. Spears are like any other weapon out there,in the hands of an expert it will hold its own against any other weapon
.
For polearms and spears and stuff they also work well for formations where you tell the untrained dirt farmer, "just hold this out in front of you," although I don't know if that was the original intent of the weapon or if the tactics are a consequence of the fact that peasant infantry already had those weapons.
I guess a specialized sword for stabbing might be effective yeah. To something up to chainmail like armor I guess?
I just find it silly to discuss the merit of which swords work best against armor because in my mind any slashing or stabbing sword is mostly effective against non-armored to lightly armored opponents, to begin with. The fact that some western sword as heavy as fuck and can deliver a blunt force trauma enough to hurt people behind armors is something I personally consider to something outside the function of a sword. At that point might as well bring a mace.
Now a question. I read that axes are more effective against armor compared to sword? What caused this? They are after all both slashing weapon right?
A thin and pointed sword would be easier to use to seek out gaps, like if you thrust it might slide along the armor and naturally find a gap easier. That is just a guess though.
As far as axes, as
fantadomat mentioned they could have a spike on them for piercing armor, but also their weight is all focused in the head so they focus more force into a smaller area which would be better than a sword for breaking mail links, for example. The blade would probably not be meaningfully better than a sword against plate, probably.
"Some western sword as heavy as fuck" is a meme though, by the way. Swords are pretty light unless they're ceremonial.
Depends on the game, in real life unlike Pathfinder plate armor is going to be better than "muh Dex build" 99.999999% of the time for example. People probably overestimate how serious an injury has to be to get killed in a fight, but based on the way armor is treated in a lot of fiction (weighs 200lb and has the protective ability of wax paper) I bet most people underestimate how good armor was at protecting you.
. Actual armour was not as heavy or wooden as games make it to be. You could do pretty dexterous shit in it,you even got more chance dodge/parry a hit with it than naked. 
