Ads are louder as an industry standard.
In 2012, USA tried to implement the CALM act, which mandated content and ads to be at the same level (“A/85”), but it didn’t play out because ads are measured individually whereas a program is measured as a whole. Complaints to the FCC are still about the loudness of ads… See https://www.izotope.com/en/learn/the-mixers-guide-to-loudnes...