srbhkshk
International Captain
That makes it a more unlikely achievement, not a better achievement. Netherlands defeating SA was perhaps less likely than England winning the whole T20 WC but the English achievement is still better.Prior to their respective series , SL maybe had 1 to 2% chance of winning whereas Ind had 30% chance of winning. This is why I consider SL achievement better.
On the topic I think it's hard to recreate the story of India's win down under with the questions over their previous series win and 2/3rds of the main team going down at various points in the series leading to an eventual bowling attack of combined ~10 or so international wickets which then went toe to toe with an attack of Cummins , Hazlewood , Starc and Lyon - all of whom are great bowlers in their on right. Sri Lanka's win was amazing in it's own right and Perera's inning one of the greatest of all time - but SA definitely weren't on Australia's level and the fact that it was only two matches on what were really low scoring pitches also made it somewhat flukier than India's.