I think people who find the Jedi’s rule on attachment awful don’t consider that being a Jedi isn’t a regular job.
They’re not space cops, they don’t put their little Jedi outfit in the morning and take it off when they get home at night while leaving their responsibilities at the door.
You are a Jedi, always, because you can’t turn off the kind of powers that come with it and not adhering to a strict code of conduct is dangerous, and not only for yourself.
It’s saying ‘if I had the choice between saving my sibling/parent/spouse or 100 people, I need to make sure that I wouldn’t let my personal feelings get in the way of making the logical decision.’ It’s Anakin saying that irrational attachment and possession are forbidden, but compassion is essential to a Jedi’s life. It’s having friends, family and lovers, and still acknowledging that if something happens to them, you wouldn’t burn down the galaxy to get your revenge.
It’s not a grand title that comes with a cool laser sword, it’s a way of life. A difficult one, which demands to make sacrifices and utter control of yourself.
It’s not for everyone, and that’s why Luke gives Grogu a chance to back out. To say ‘alright, maybe I can’t do that and would prefer to stay with Din’.
And it’s not the end of the world if Grogu doesn’t become a Jedi! It only means he’s not ready to adhere to the philosophy that comes with it. And it's not the end of the world if Grogu chooses to be a Jedi! It only means he will have to learn that some things must be more important than Din when you become so powerful.