Diablo 2 Resurrected

I completed Diablo 2 a couple of years ago on PC, and I even gave Diablo 2 Resurrected a go when it just came out. But turns out all that time I played it wrong.
For a normal person, it’s obvious that unique items are better than rare, and rare is better than magic, and magic is better than common. This is how that system works in every ARPG for ages now. Not in Diablo 2, though. The most coveted items are commons with sockets. In original game, you would put some gems in those slots, fun customisation. But in Lord of Destruction they introduced runes, which, if socketed in a correct combination, would create a unique item, but without the RNG involved, and often more powerful.
I also didn’t understand the attack speed at all. For example, if item has “+5% attack speed”, it doesn’t mean your character will attack 5% faster, no. There’s a concept of “breakpoints”: at a certain percentage, a single attack animation frame is reduced. So you need at least “+9% attack speed” in total to see any benefits, then +18%, then 30%.
I already knew the theory behind “player count”: you can multiply enemies power up to 8 times, in order to get higher drop rate and experience. But how a single character can survive a challenge set for 8 players? One of the videos explained it well: if basic enemy has 10HP, it doesn’t matter that at highest difficulty it has 80HP, as long as you can still kill it in a single hit. And the builds revolve around stacking so much damage through skills and runewords that is stop mattering.