Maybe Asguardians age like dogs lmao, 4 years to a normal year. Jotunn are the opposite - 4 years to a notmal year. Loki uses the World Tree standard year while Thor is like “yes this is my fourth birthday this month i will not elaborate” and both are for the drama.

if they use Asgardian years on Asgard and there are 4 birthdays in a year that means Thor is actually only *checks watch* around 300 years old