Blizzard has stated that D2R will release by 12/31/2021 and today refined that to the second half of 2021.
It depends on how a charm inventory is implemented. Many people fill their inventory to the brim with charms, increasing their character’s power. If the charm inventory was only half the size of the current inventory and charms only “worked” in that inventory, the game would actually be harder not easier.
The issue is that there is no way to please those who want the status quo versus those who want changes. Separate game servers seem like the best win-win solution.