I agree with you that Lemmy should have it (and seems like it will in v1.0), but the devs are more likely to see our feature requests if we submit them on Github instead of as random posts in different communities

and Github makes it easier to prevent duplicate submissions

Yeah, but they'd probably be better submitted as GitHub issues instead of posts here, or in this case searching for the already existing issue

So many upvotes too, that's crazy

The problem is just when someone in the past said “you should join <forum x>!”, you were always able to just immediately go to forum x’s signup page and sign up. But if someone hears of Lemmy, and goes to join-lemmy.org, there is no way to go to a signup page directly.

People should probably stop saying "join Lemmy", and instead link directly to the site/instance they suggest

User should create an account on one server

Mostly this. Some people might want a few accounts but those would be hardcore users.

the password/cookie should still work even when awaiting validation, password is set before the email is sent

maybe I'm misreading what you're saying, but we already have this, works the same way as Reddit

https://join-lemmy.org/docs/users/03-votes-and-ranking.html

the Summit app does it too

Will Lemmy can become easy like Bluesky? Are there plans like that?

I'm not a Lemmy dev (well I've made a couple of small commits lol), but this type of question can be hard to answer from the inside of a project.

It would probably be easier to answer a question more like: "Do you plan to implement feature XYZ in order to be easier to use like Bluesky?"

https://github.com/LemmyNet/lemmy/issues/1883