That's probably a plot point though. Mr. Incredible was all ready to go back. Helen was fine being in a family and letting things be. However, the rich guy trying to get heroes back thinks that she will provide better optics.
This creates tension where Helen has to deal with mixed feelings about going back (but does it anyway because Bob wants heroes to come back, so she is doing it for him) while Bob deals with his jealousy over that and adapting to his new role (all while having to support her despite these feelings because he knows what she is doing is right and will help heroes).