..and if you are just speculating, it would probably be more accurate to reference the boiled egg eaten during Passover as a symbol of korban chagigah (festival sacrifice) that was given in the temple.
The challenge with the speculation above is that I’m aware of, only the Eastern Orthodox church bans eating eggs during Lent, the Catholic church doesn’t.
I’m definitely a believer in the notion that various traditions (an even etymologies) support each other, so that many traditions are not “this OR that” but “this AND that.” Therefore, the notion seems quite plausible, that paschal egg contributed the degree of seriousness with which Eastern Christians treasure their Easter eggs.
But yes, dairy, fish, and meat were abstained from traditionally in the Western Church, as well.