That would maybe depend on how broadly you would consider the act of taking cues really is.
It’s probably definitively already over with by FFVII. If FFVII was a departure of Final Fantasy from itself, it must have been a departure from Dragon Quest too.
I could maybe make a case as well that the two series haven’t been as lined up as they were in 1989 at each of their third entries. So it’s the zenith if not the endpoint.
But I don’t know, maybe it is the end point? At least in a major way. I don’t feel there is a whole lot of stuff with obvious parallels in DQIV and FFIV, even less so as both the series make progress.
DQV and FFIV following the ups and downs of a main protagonist for a good while but FFIV was a good deal before DQV. FFV returned to a game centered around a Job system (FFV) sooner than Dragon Quest did (DQ6).
I can’t really think of anything all that substantial in terms of parallels between them after the third entries in both series except for those particular moments in FFVI where the party splits and you’re playing through synchronized story threads one after another until they converge back in the same place, echoing the brilliant opening sections of DQIV. Except FF makes a meaningful development on that idea by weaving those sections through the main story and sometimes even lets you choose what order to play them in. I’m one of those sticks in the mud who doesn’t care for FFVI all that much but this is one of the pretty unimpeachably neat parts about it.