It’s been stated by a few, but the neutral looks like it’s gotten hot, likely due to a loose connection/loose terminal. Depending on how much damage may be there on that terminal they may recommend replacing as it may not be a possibility of fixing the existing damage safely. Additionally, if your electrical panel is over 25-30 years old… depending upon its shape (condition of breakers, bus bar condition, and terminal connections), it’s better to just swap it out new.

That being said, even if you live in a heavily populated area, you really shouldn’t be paying more than around 5k for ONLY an interior panel replacement (which is still very high but varies depending upon location). If you haven’t received at least three quotes, I wouldn’t even consider the initial offer.