Still wrong.
They are extremely trivial.
This is more wrong than your first point because it’s 3/6 heroic once per week from vault, 1/6 farmable.
This is disingenuous, because M+ awards 0.4 items per person while a delve awards 1.
Raids have a cap on running it. M+ and Delves do not have a cap on running it, but M+ is limited to a lower reward track at the end-of-dungeon compared to the vault. Also, M+ and raids both provide a challenge at rewards levels.