"Be yourself" doesn't really mean anything. I do agree with your assessment of the healthiest interpretation of the advice, and I think this is how people mean to use it. That said, plenty of people misinterpret the advice to justify not changing too, and that's what the article means to address.

>"Be Yourself" does not mean be your bad sides. Nor does it mean be static and never evolve. It means evolving while still respecting the person that you are. This includes shedding bad habits.

Sounds like an empty platitude then, if it takes a whole other sentence to explain it.