I have taught from Nursery to Year 6. Did the good old 4 year Education degree many moons ago, specialising in Early Years. For those teaching children of statutory school age and above, I do expect a degree. By teaching, I mean those who hold Qualified Teacher Status. Thus I expect English and Maths GCSE as standard.
But when my dc were in day nursery and pre school, none of the staff were qualified teachers with QTS. They all held relevant childcare and early educators qualifications. All very competent.
For Nursery schools and Nursery classes attached to primary schools, I would expect a mix of teachers with QTS and then other suitably qualified staff.
So to answer the question, yes I expect a Reception teacher to have Maths and English GCSE. Just as I expect of anyone with the job title of Teacher to have QTS following on from Higher Education.