how much maths and physics is needed both to pass ATPL then day-to-day when qualified?
About the same as for passing the exams for and subsequently driving a lorry. I've got both licences, hence how I know.
Once again, in spite of certain pilot training outlets calling their offices "campuses"
, and everyone using all those academic terms ("college", "graduation", etc.), and trying to dress their customers in silly white shirts, this is nothing more than a vocational qualification. If you got through secondary education without major problems, your educational level is already well above what is needed for a pilot's licence.
What really matters for becoming a successful pilot are the so-called soft-skills: teamwork, decision making, communication skills, etc. And of course, experience.