Yeah I noticed the zombies movement was a little too tuned up as well. Like you said feels odd on early rounds as encountering sprinters is something that just never happened at those levels. You can kinda give it a pass if you start with a loadout given you have more firepower early on to care. But that doesn't really solve the problem for people playing the game with the starting pistol as the game was intended as they'll be a lot weaker in the early rounds and could get knocked to an unexpected sprinter or few. Especially because zombies cannot be knifed thru the windows so your only option in the early rounds to maximize points is to let them all out (and hope the first few you knife don't drop a nuke that clears the rest). But yeah that sets you up to get surrounded if you're not careful. Not to mention these sprinters are faster than the OG game. In BO1 you could walk faster than zombies ran (as dumb as that sounds); so maybe the move speed buff was intended. But yeah it makes early rounds super tense for no reason, and basically requires you enable 'toggle sprint' in the settings or be holding sprint at all times to keep distance.
My only issue is the speed kinda fucks up trains as the spawn limits and rules are seemingly different in this game vs BO1. I'll be on Kino training on the stage as per usual, but the amount of times I get surrounded by nearly all directions and have to take an alternate route is crazy. Could just be me playing zombies again for the first time in a while; but I swear it is not how I remember it. Which is fine to an extent (I enjoy a challenge and welcome change); it just feels off to my muscle memory. But yeah since in later rounds a majority of the zombies are running; it makes it wayyy easier to get surrounded and quickly. They get to your position so fast and in numbers it is overwhelming at times compared to how the OG game was played. And then this is made worse because there is no ability to cripple the enemy so you can't even slow them down with nades or items with splash damage like Ray Gun. (I hope that'll be added at some point, but idk).
Also whatever that dude said about bhoping; I think just got nerfed as well. I never used those techs as they were never needed for BO1; but in the latest patch notes it says they added something called 'jump fatigue'. So if bhopping around was your go to to get around this; it looks like the dev doesn't want you doing that or as much. So for all we know the dev wanted there to be a harder zombie experience in some aspects. Still feels off for returning players expecting a truly OG experience so it'd be nice if we could toggle some settings like this to return the zombie movement to the original BO1 speed. Like having the option to challenge yourself would be cool, but locking players into it simply cause the dev has some preconceived notion of how the game should be is kinda hit or miss. And that goes for many of the added QoL options on maps. Some are welcome, some are just making the game easier/harder; but all should be toggleable so people can play exactly how they want🤷♂️