Yes correct. I tried both and was annoyed that the zombies aren't deadly enough. Like "oh we have this serious virus but you can survive getting bitten multiple times"
With the idea I wanted less of a story (and let's be honest both games and their successors did not have good ones) and more of interesting escape attempts (find a drill and move underground, or dress up as someone from the military or idk get catapulted with a parachute)
A procedurally generated escape the city third person zombie shooter with several randomized unique quest lines that can be discovered by scouting the city. Each quest line leads to a different escape route. (Military has surrounded the city)
Zombies should be 28 day later, one touch and you are infected zombies.
Maybe add some basic crafting and possibly coop or pvpve elements. One escape should take only a couple hours. The randomness gives the replayability. (A bit rogue like)
Get "darn toughs" - expensive but warrenty for life.
I know all the games you have listed. I havent played them but I can tell that none have the features that I am looking for.
Prohect Zomboid comes close in terms of environment but has a different gameplay approach.