Slimming down was always, imo, simply about the number of working royals being paid by the tax payers, rather than properties (though they only own a few - the rest are rented albeit cheaply) and occasions.
Back in the 80’s the number of working royals, or those expected to be working royals, all being paid was high, and expected to stay high.
You had the Queen & Philip, the Queen Mother, Princess Margaret, Charles & his wife, Andrew & his wife, Edward & his future wife, Anne, D&D Gloucester & Princess Alice, D&D of Kent, Princess Alexandra.
The slimming down was meant to signify that it would go on to be Charles, his wife, plus his children & their wives along with th Andrew, his wife but not their children, Edward and his wife but not their children, to pull the numbers down significantly. No cousins of his generation or of his children’s generation.