I personally favor C9 in that match, but the difference in experience does make people question that decision a lot.
Narrate and bang were two of the biggest question marks for SEN coming from Bangkok, there must have been hundreds of "They can't possibly replace TenZ and Sacy" posts here and on Valcomp. And since those two are also doing really well right now, people are optimistic.
I don't personally put any stakes into the "C9 always chokes in play-offs" narrative and maintain the opinion that they looked very competitive against stronger teams (could have won, even), but you never know.