Photo: a fengshui easter egg on Ali express
Theresa May PM wants full on traditional egg hunt while others are moving away from Christian stealing of other people's customs and traditions. Especially now that some are more prosperous. There is a link with population prosperity and fall in religiosity.
In spring there is cause to celebrate life and its regeneration. Hormones change with electromagnetic radiation from sun, and eggs are produced.
Chocolate eggs are nice way to mark spring and that is it. It was pagan goddess Ishtar who was presented by her worshippers with fertility symbols eggs and rabbits because she was Mother Goddess. Apart from Ishtar she had other names such as Ceres (yes, breakfast cereals named after her), Diana, Venus and others. The Resurrection myth also predates Christianity.
As to the complex subject of human identity, religion may be there but it may not.