Sprint is not the only way to make the game play faster or to even make a player move faster.
Sprint is not the answer in Halo because it does not mesh well with Halo's long kill times.
^ This. In fact, H5's weapons were purposefully designed to kill faster because of sprint (and thruster to an extent as well). And smart scope was slapped on every weapon to give them all a range boost as a result of maps getting stretched from sprint.
It's a vicious cycle of one mechanic, all for the sake of "immersion".
You are listing changes, but what exactly makes them vicious? Because the automatic are now useful? Because it's different from how it's been until now? Where is the problem?
Different =/= Worse
Others prefer these changes. Some loathe them. It all comes down to preference. 343i prefers the modern version. You do not. Does that make the changes objectively worse?
No.
Sprint is the root of several branching problems. 343 has attempted to bury those problems through unnecessary changes that affect the game's balance.
Because people could get away faster and more easily, weapons weren't killing players before they could flee. As a result,
weapons had to be buffed to kill players fast enough before they could get away.
Sprint also requires maps to be stretched so that players aren't running into each other every 2 seconds. As a result, sightlines grew longer, and weapons that were limited to closer ranges were even more limited. So every weapon was given smart scope, with some receiving an accuracy boost to further benefit them at longer ranges. I'll admit that full autos needed to be buffed, but 343 didn't buff the full autos to benefit the weapons,
they did it so sprint's effects on map size, and by extension, weapon balance, didn't seem so severe.