People are looking more at this:
Goodra managed to tie against Slurpuff, a Fairy type that uses Flamethrower, or rather, Goodra's two biggest fears. Yet in spite of that and not battling for about 60 episodes, it still tied, especially when half its moveset was restricted (we have no way of telling if Slurpuff is truly his weakness). Likewise, Bisharp was the worst possible matchup for Goodra due to his slow bulk up against Guillotine, but he managed to deal enough damage and set up a Rain Dance that allowed Greninja to mop up Bisharp in one hit.
Likewise, Noivern was a Pokemon that had problems flying when we first met him...yet he showed mastery of the skies against Salamence, at least to being able to tie, when both sides were taking double damage. He did take the fall against Weavile (which does have a 4x weakness), but that all served to power up Hawlucha.
The Kalos team worked better as a cohesive *team* than on necessarily their individual merits (though 2/3 of their individual merits are also pretty strong).
Likewise, the biggest problem with rating any of Ash's SM team against Kukui though is how featless everyone but Incineroar is. Lucario literally just jobbed a few episodes prior, and Empoleon had never even been seen before, same with Venasaur. So it's hard to actually test how strong they are, especially when 90% of the SM teams feats come from the League itself (in fact Naganadel's only battle was Kukui) so there's no comparison that we can make there, and the Kukui battle didn't really focus on any character moments since they'd had them all prior, save for Torracat.
