And I saw that all labour and all achievement spring from man's envy of his neighbour. This too is meaningless, a chasing after the wind. (v4)
Envy, like pride, has a thousand faces. I can find myself envious of lifestyles, opportunities and backgrounds. Envy can often drive us to make decisions we later regret or fuel an attitude we find difficult to shake.
But this passage is speaking of more than simply 'coveting your neighbours wife or setting your desire on his house, land, ox or smartphone' (Deut 5v21).
This passage is speaking of the futility of labour & achievement that spring from envy. Envy that results in 'wanting what others have' is never satisfied by getting what they have. Envy can be like chasing after the wind.
Envy is diminished when you come to terms with what you have right now, is God's economy for you, right now.