I have a 2015 Audi TT that has done 26,000 kilometres and has developed a frayed driver’s side seat belt. The dealer’s first response was that is was fair wear and tear, but I beg to differ. Surely a seat belt is designed to last longer than 26,000 kilometres and normal use?
You would expect the belt to wear to some extent, but not to fray. A frayed belt could be dangerous if it were to fail. Based on what you say it would seem there’s a problem with the belt or the installation. Take it to your dealer and show them what it is you’re concerned about.