Sinner and Alcaraz predicted major count

I’ve been watching tennis since 2017 (the first full match I watched was the 2017 AO final). I’ve never seen a player be more dominant than current Jannik Sinner. Given Jannik current dominance it had me wondering what both his and Carlos’s career accomplishments look like.

What are the odds both Carlos and Jannik finish with 20+ slams?