If you like to RP and are a fan of immersion, do this: purposefully encumber yourself and enjoy the beautiful world of BG3 at a nice, leisurely pace. Walking is the most evolved form of movement, both in video games and in life, so why wouldn't you do this?
Consider your options. You could take command of a party of mighty adventurers, and then send them goofily jogging through halls and forest lanes, limbs flailing like a group of ungainly children, forever trotting towards the horizon at a frankly bizarre pace, not fast enough to convey urgency, but far too fast to convey normalcy... OR... you could make them walk. You could travel the beautiful Autumnal forests and ancient castle halls at a sensible, natural pace. You already look like real people (basically), so why not perambulate like real people do?
Real people don't run everywhere. Just try walking. If you don't like it, you've lost nothing but a few meters of artificial distance. If you do like it, you'll appreciate the game even more. Also it makes combat more challenging.
