In other words, they're trying to keep the variance of the distribution of salaries constant over time. Limiting economic disparity have always been beneficial

In other words, they're trying to keep the variance of the distribution of salaries constant over time. Limiting economic disparity have always been beneficial to the group I believe (I don't have data for that). In the same company, the top should not be paid x% more than the lower salary. In the same country, the maximum wage should not exceed x% more than the minimum wage (after taxes).