I'll start saying that C9 had a GREAT run, and I appreciated their play in these Worlds
The problem is that both NA haters and fanboys are not being objective when evaluating it, and they should bring back their performance to the reality
C9 showed how by not being your typical NA team, NA can succeed at international level, and this is the culmination of what they have often done in the past which made them by far the most successful at Worlds in NA history.
They are the NA team where players don't assume a smug attitude towards their success, are generally more positive personalities, they are the NA top team that invest in and trust the most in rookies, they are the one with the more unique and aggressive style compared to the other Korean copycats, they put emphasis on individual play even though it can backfire, and they are a pretty solid team all things considered (as showed in the past with those hour long grinded wins, and also this season they had a lower potential performances than peak Vitality but they were able to edge it out in the end with their superior experience)
C9 didn't get success because others were bad, they got success because they were very very good
Having said that, it is also true that C9 were really lucky, as they are the lowest ranked ever team to get to semifinals, when you look at the rankings of World performance in any given year
No team ever got to semifinals being arguably only the 6th best team in the competition; even what were labeled by NA fanboys as the weakest semifinalists in previous Worlds like H2K in 2016 or FNC in 2013 or WE in 2017 were at worst the 5th best team in Worlds that year....and C9 lucked out in facing the 7th best team at Worlds in quarters despite finishing 2nd in the group stage
C9 got also lucky to be favoured by VIT litting up the fire in their group and overall in the entire Worlds (alongside G2) which estabilished the style that C9 also took and hurted the Korean competition that C9 had to overcome to get to semifinals, while VIT itself was penalized by their high risk style when faced a team with similar style but more experience to get over the group stage while being likely weaker than peak Vitality as yet said
C9 run is historic for the region and NA has to celebrate its players and got the right lessons to improve to higher levels their performances, but you shouldn't overblown or downplay their achievements or the achievement of the entire region, NA is still way behind the top 3 regions (KR, CN, EU) and in overall rankings is only gaining spots relatively to LMS region that got destroyed by Garena/Riot decision to competitively destroy that region by splitting it in multiple ones (imagine fielding 3 teams made by the best of LMS, Vietnam and SEA region alltogether rathern than them being split).
100 Thieves was terrible, and TL as the typical NA superteam looked clueless and basically had no chance to get through a relatively easy group when they had to just prevail in the head to head vs the worst version of EDG ever at Worlds (TL beat them in week 2 when EDG had dropped their concentration after upsetting EDG and guaranteeing their ownspot in quarters)