I agree with the sentiment and think this is a real problem.
To call yourself Catholic without qualification, you should fully accept the teachings of the Church and all that means. Claiming to be Catholic without qualification when you are not brings scandal to the Church. Non-Catholics will say “yes, he/she is Catholic but doesn’t believe xxx so not all Catholics do.” Or they may say there is disagreement among Catholics.
Of course, we do not have the option to define the Catholic faith any way we please. There is no disagreement among faithful Catholics.
I can think of 4 categories of people who should not call themselves Catholic without qualification: (1) lapsed Catholics who have fallen away for whatever reason, (2) practicing Catholics who privately hold one or more “exceptions” to Church teachings, (3) misguided Catholics on a personal crusade to pressure the Church to abandon settled truth (e.g. accept abortion, homosexuality, women priests, etc.) and (4) Catholics who misrepresent the faith to further personal agendas (particularly politicians).
This last category brings great harm to the Church. Their actions are often gravely immoral and despicable of themselves, but to claim they are faithful Catholics (when they clearly know they are not) is evil and very upsetting.