Alcaraz with 6 slams would remain 1 slam ahead of Nadal at the same age.
And could realistically reach 25. Nadal won 0 in 2015-2016.
Just needs to keep Nadal's pace and add one in each of those gap years.
He will only Sinner to contend with him next year, djokovic will be finished for good, and Musetti/rune/fonseca/mensik/vanassche ain't it.