Sorry, consumers are not responsible for 'doing their own research' - corporations have an obligation to disclose any material defect in a product or service that would otherwise affect a reasonable person's decision to buy.

If the home you're selling has a leaking roof, do you feel you have no obligation to disclose this to buyers? They should be required to do their own research, so it's caveat emptor? Guess what - the law disagrees strongly.

United is positioning window and aisle seats as a premium product vs middle seats - however some of these products contain material defects that would otherwise affect a reasonable person's willingness to pay that premium, hence the defect should be disclosed and the buyer can then make an informed decision.

I've seen other airlines include this information on their seat maps - so there is precedent to expect this disclosure.

Whether the lawsuit is successful or not, the argument itself has merit. Should Basic Economy fares be sold without full disclosure? Caveat emptor, you better join Flyertalk and memorize those fare class codes so you know what you're buying.