Airlines are required to provide price taxes and fees up front, it had its own legislation around 06(?). The rest of the things they’re now charging for like baggage, a non-middle seat, etc. that used to be included are theoretically optional so they don’t have to include it.
Airlines just need to be federalized officially, they’ve had two bankruptcy cycles in the last 15 years, and the industry has no ideas or interest other than adding things to the list above that are currently included that they can then charge you for. Canned air from Druidia is next.