One issue with your statement... Saying "again" implies they were ever good in the first place. Spears have never been good in game, despite one verified dueling manual of the late medieval era placing only the dagger and buckler combination higher than the pike for 1v1 duels. In England i believe it was a sheriff told the king to recommend the quarterstaff as the defensive option against brigands, as its useful in multiple roles, does not present aggression just by having and is very cheap. When people doubted the quality of protection it could offer, he had a demonstration set up where he proceeded to destroy 3 men coming at him with daggers using what is really just a long stick. .
These things are great for historical knowledge or practical "just incase this becomes Mad Max" backup plans, but less so for games. It is very difficult though to balance because if a spear can hold someone off at range, do great armor piercing damage with a thrust, and effectively be used like a staff to push them out in close range, it becomes the default weapon for everyone. Unfortunately game mechanics somewhat have to dictate the situation instead of reality in this case. Though I'm certain a better job can be done than currently, balance is a major concern.
Games are full of this stuff though. I am aware this has nothing to do with Bannerlord itself but for context of how balancing has to work lets look at shooters. Pump action shotguns in game? You shoot then for some reason pull the weapon back against your body, make it vertical and do a very exaggerated chunk-chunk slide, like the breech block weighs about 10 pounds and is rusted shut, before leveling it back out again to shoot, about 1 shot every 1.25-2 seconds. Do you know how fast you can use a pump action shotgun irl? 5 rounds in 4 seconds is a rate that can be considered "careful." The gun never leaves the level and the only thing that moves is your forward arm to do a simple quick slide motion that takes less than a tenth of a second. Because if they let you shoot the gun like it would realistically, you would destroy everything in close range so fast its stupid. 00 buckshot is basically the same thing as a .380 bullet, so its like firing 9 handguns at once at a target.
But on that note, maybe just making all weapons crazy is the correct avenue. If everything is stupidly powerful, nothing is overpowered. Currently, where are the halberds, poleaxes or other two handers that are not super slow, have a strong ranged swing and a reasonable thrust attack? I can make a falx doing 150+ damage with a 110 swing speed and 155 reach. Maybe other weapons need to be as devastating across the board? Having a halberd that could do 120 damage, 95 swing speed and 185 reach sounds fine to me. One handed swords that swing at 120 speed but have lower damage or armor piercing but still make it to 105 range? Great, bring it.
Bows are the only weapon currently performing both in a balanced manner and to expectation, imo