Honestly I don't understand why everyone expects FW to be weak. Every year people claim LMS is the weakest region, and have no expectations of FW, and most of those times the surprise. But every year we go back to considering them to be weak.
Basing the strength of FW on worlds 2016 is tough. They were incredibly dominant in the early/mid game, having large leads, but they just couldn't close the games out. They arguably should have taken the #2 seed in the group, but they were their own worst enemy.
After worlds it seems they quickly fixed this problem though, because they completely sweeped IEM Katowice, which featured some of the strongest teams in Europe.
Looking back at MSI 2017, people claim they weren't strong or convincing, but what do they base this on? They went 1-1 against TSM (and FW's win was a lot more dominant) and won the tiebreaker. So if anything, FW had a stronger performance than TSM, who is now also in Group D. The only reason FW didn't make it out of semis was because they faced SKT there.
The LMS doesn't have as much talent as the other regions, therefore the competition and practice during the split isn't as good, but basing FW's strength/weakness purely on this doesn't do them just.
I feel like FW has just as much chance to make it out of groups as TSM and WE do.