The Color walk statement is used as brainless propaganda without knowing the actual context
Oda is referring to the SH Crew as The main protagonist and
THERE WERE ONLY 3 SHs till then. USOPP has not joined then.
The quote is from Page 28 of color walk 1
And here is the timeline for the pages mentioned in Color walk 1 table of contents
So the quote is from before 1st December 1997
Usopp arc serialised in 1998
https://onepiece.fandom.com/wiki/Real-Life_Timeline
The Romance Dawn trio is fan made