The reason they use sprint is to make you choose between running fast or shooting. Is it just that people hate having to make that choice?
Would you be OK if they removed sprint but made it so if you're shooting a gun you slow down a lot?
Why should shooting be tied to slowing down?
The best way to explain why reason I hate sprint is like this:
When I played Halo 2, I could run from point A to point B, while shooting someone at Point C, while checking my flank back at Point A, then chucking a grenade to clear point B- All while moving at top speed the whole time.
When I play H5, If I run from Point A to Point B, I have to look at Point B the whole time. Oh and I can't shoot anyone, check my flank or throw grenades without slowing down and killing my vibe.
Simply put, I find the H2 scenario to be Allow for more dynamic scenarios, and thus more fun. It also also the dev more freedom with map design.
If someone asks me if a want to Shoot people or move fast, my answer will be "why not both?" every time. Why would I want to have half the fun in any given moment?