Why Do People Complain So Much About Red War?

This is a genuine question coming from me, no hate intended. On other social media platforms I see so many people complain and say since they vaulted red war, that they stopped playing Destiny 2.

What is the reason for this? I feel like people stopped playing the campaign entirely by the time that warmind came out. There is absolutely no reason to run the campaign unless you were doing it for “fun”. But the game has evolved so much since then and there are much better campaigns or missions in the game that are more fun.

Campaigns have almost never had a reason k be played other than when the expansions dropped. I haven’t played a single campaign over again, other than when they drop.

So if there an actual reason for running the campaigns, or do people just like to complain?