At level 1, every character class has access to some simple weapons. Monks, wizards, and druids have the most restricted list of access. But typical melee classes like fighters have access to both simple and martial weapons, and with a single feat could get access to exotic weapons. However, characters usually get at least one new feat every two levels, sometimes more. And if you want to make an efficient build, you will have concentrate on a single weapon. There are feats like "weapon focus" or "weapon specialization" or "improved critical" that don't work for all the weapons you are proficient in, but you have to specify which weapon the feat should apply to.

At level 1, there isn't much of a difference between a regular longsword and a regular battleaxe, except for how they handle critical hits. You can perfectly choose either one of them and be fine. But a few levels down the road, you'll be stuck with your choice. If you chose longsword, you might end up having a regular +1 longsword and looting a +2 battleaxe with some interesting additional effect; but because you have specialized in the longsword, you won't switch to the battleaxe now, unless you pay for an expensive respec.

Now Pathfinder: Wrath of the Righteous has 56 different types of weapon, but you group only has 6 characters. So the chance of any random weapon you find to be completely useless to your group is quite high. The situation with armor is a bit different, but it also happens that an armor has a magic effect that would be good for one of your characters, but its armor type or other stats aren't useful to that character.

In the end, your group in Wrath of the Righteous ends up selling most of the loot. Which is a lot less interesting than finding loot you can actually use. In a pen & paper game, the dungeon master simply cheats and doesn't hand out incompatible loot. But in a computer RPG, the devs don't know which weapon you would specialize in, and so they just sprinkle a bit of everything.