You were sold some horseshit and you decided to eat it.
- First, because the "turn limits" weren't on every mission. Maybe half of them at most, if even that.
- Second because the objective system was modular (with some objectives being timed, but then you had all the time in the world to complete the rest)
- And third, because you caved to the pressure of an imagined and perceived unfairness without giving the system a chance, otherwise you'd have quickly learned that the "time limits" were plenty forgiving enough and they actively made the game better.