The article says that GLONASS time counts days from zero to 1461, then resets back to zero. This is 4 years if we think leap year is once 4 years. But it is not. Leap year is once 4 years, but each 100 years it is not, except each 400 years it is. This is on average 365.2425 days per year not 365.25 days per year. Is GLONASS not long term thinking ahead enough?

GLONASS also depends on leap seconds, which is why Russia is opposed to eliminating them by 2035.

Leap seconds are completely arbitrary by committee, aren't they? I'm curious how there could be a technical dependency.

GLONASS transmissions have fields for earth orientation parameters that are too small to allow for unbounded DUT1: it has a built-in assumption that its system time is close to earth rotation angle.

See also: http://www.aholme.co.uk/GPS/Main.htm