Yea, I think you will have needed to see Breaking Bad in order to fully enjoy and understand the show. If you haven't seen BB, sure, you can still enjoy this show. But it will just be a show about a random attorney, with other random characters involved. If you don't know what eventually happens to Saul and how the other characters fit in, I feel like you will be missing a ton of context and meaning to what happens in the show. I'm sure it would still be good to someone not seeing BB, but they will be missing out on a ton.
Take last night for example. The reason why it was so entertaining is because in every scene we are comparing Saul to how he was in BB. It's interesting to see that he hasn't hit his stride yet and that he's not as skilled/polished/confident as we know he later becomes. IF we didn't have that context, it would have just been an episode about an attorney who has some weird quirks.