Well, yes and no. :) You're absolutely correct about the different ways that different computer monitors display colors. There are even differences in the way our eyes perceive different colors. That is one way the egg color chart is helpful.
While blue eggs are what the standard requires, "blue" covers a wide range of colors: all the way from a very pale, nearly white, blue to a very dark with greenish tint blue,.
What you want to avoid are pure white eggs, or eggs with any brown. Although, given a choice, I would much rather see white or very pale eggs in the nest box, as it is much easier to darken that color in the ensuing generation, than see brown in the nest box. That brown can be very hard to get rid of and I would just cull a hen that laid it.