I don’t think you gain anything with the flashbacks.

You have Alec Guinness and Mark Hamill, two great actors, together.
If anything we want to see more of them, with less distractions, not cut away to other stuff.

I get that you want to do one cohesive saga.
But remember that Obi-Wan is not being 100% truthful and tells it to Luke (“from a certain point of view”).
On the prequels he’s also like that, he’s not a 100% pure character.

So I’d keep that dialog as it is, since it gives the saga a more mature undertone.
The Jedi are “good” but not saints 😉