What’s the difference, in the end? Are wages after accounting for this worse for Norwegians than Danes? At the end of the day any mandatory paid holiday system means the employee does less work so is less valuable to the employer (benefits of returning refreshed notwithstanding - in any case all these effects should be the same regardless of what financial rules govern it) so the employer might want to pay them less in total.

But this should reach an equilibrium where the cost to the employer is similar for similar amounts of labour, resulting in similar pay.