the game "feels good" that is true, but it's not the aiming controls that do that. it's the audio visual design (animations of the gun, the sound of the gun, hit response markers and sound etc)
but just as a demonstration for the bullet magnetism in Destiny 2, and it's basically the same in Halo if not stronger in some circumstances.
and I will remain with my opinion that if Destiny 2 wouldn't have this much aim assist and bullet magnetism, people would not say it plays well. because I have played shooters with similar controls but with (let's call it) normal aim assist, and it is almost unplayable.
and yes, the clip here is on Mouse on PC btw. because if mouse didn't have this massive magnetism then controller players would fry them to no end. the same reason why Halo Infinite keeps the bullet magnetism on Mouse and Keyboard.
in Halo's case it is because the BR (the most used weapon in competitive modes) basically aims itself, barely needs input from the player, just aim at the general direction of the enemy.
I think in Halo's case the Commando (a similar weapon to the BR in terms of use cases) was specially introduced to give Mouse players a weapon they can dominate with as it has very little aim assist on controller and has a faster TTK and a higher effective distance than the BR