As someone who also knows how to calculate THAC0, I respectfully disagree. I won’t argue with anything you said, because those are valid points. Just a difference in play style.

Back in the day, we simply skipped, simplified or avoided any of the more complex formulas. We wanted to keep the party moving, and I think the new rules do that better. Roll a 20, high is good, low is bad. That’s all you need to know, and you can focus more on coming up with creative, fun solutions rather than worrying about all the modifiers and restrictions that limit what you can do.

I don’t think we ever ran any real large scale battles, or, if we did, they just got zoomed in. (There’s a massive battle going on around you, this is the tiny portion of it on front of you, and the DM will tell you how the rest plays out).