Can a Couple have too much in common?

I've been doing some editing work lately. The last manuscript I read has a love interest who I feel is a little too similar to the protagonist. Obviously a good relationship should be built on mutual similarities, but the similarities here are a little on the nose. Their personalities are similar (both are Phlegmatic) and their backstories are almost the same. Both are children of divorce. Both have stepparents who have annoying pets. Both their fathers went into the same line of work. They're not 100% the same. For instance, they have different hobbies and career goals. However, that doesn't seem enough to differentiate the two, at least to me. Should I suggest they change the characters a bit so they aren't too similar?

I think that it's hard to say without seeing how it works out in execution. In and of itself, I don't feel that it's necessarily problematic.

Of course, you can always discuss it with the author, see how they feel about it, or find out why it is as it is.