It is literally the same thing: the AI cheating to have an advantage in the form of massive troop numbers. Those special event troops almost always scale to your realm/levy size, the mechanic hasn't changed much since 2013 like you imply and has gotten worse over the lifecycle of the game because PDS keeps adding in new doomstack events for "challenge." People complain about AI armies in Bannerlord just appearing from nowhere when they don't. Saying CK2 is a better example when it does create troops from nothing, then have those troops not suffer from basic mechanics like attrition (otherwise they'd faceplant every time) is nonsense.
CK2 cheats in the exact way you think BL does (it doesn't, except for like 10 troops on spawn) then it cheats another way because the AI is too dumb to manage otherwise.
No, it isn't "literally" the same thing and I explained how, and even pointed out the "proof" you had for one of your claims was old as dirt and expansions old + balance patches old. That was 8 years ago. 8 years. And yes...it has changed
considerably over the years and any AI not getting attrition was due to bugs (you can confirm this by just checking the forums, in which the devs respond to these threads to say that that's not an intended feature) or balance issues, which had been patched/changed. I play this game all of the time, and have nearly 500 hours into the game. The only time AI does not get any attrition is when
special events spawn or
situations like that, which are not all that common. Any other time AI has low attrition, is due to game mechanics which are open for players to use as well, such as maxed out defensive trees.
You can learn a bit more reading this (which mentions one of those event or culture specific situations in which attrition is not a thing):
https://ck2.paradoxwikis.com/Attrition
Players can further avoid this problem by keeping watch on provinces for seasons, supplies, religions (pagans etc) as well as, if it is their territory, buffing up their trees. On the road, players and AI, can help stave off attrition by looking at the supply amount in each province and even avoiding costly routes (rivers, mountains, snow etc). This is not something only available to AI. It simply isn't. If a player is smart enough to take advantage of it, they do. If they don't, they're going to get steam rolled by anything that moves, regardless of if its 10k or 30k.
Bannerlord, on the other hand, has this problem spread out through
all AI constantly. It isn't a "
oh, maybe this will happen, better be careful!" it's a
constant problem. Beat an AI, they come back tenfold.
Always. Instead of handling this seemingly endless population in Bannerlord or restrict it somehow, they just allow AI to recruit endlessly immediately after loss. So I say again: not the same thing and you know it. But whatever floats your boat, huh?