Simply put. Yes.
I have the ratings for every single episode, even the nigh-impossible to find 9/12/01 rerun. If you analyze the ratings from Season 4, besides seeing that it was down over Season 3 you'd see a big drop down from Fall 97 to Winter 98 and when you parse the ratings out further, you can see what really happened.
Ratings for new eps in Fall 1997 were up +0.28 over Spring 1997 (+6%), but ratings fell -0.90 in Winter 1998 (-18%). Take out "Scorpion, Part II" and you get +0.12 & -0.74 respectively (+3%, -16%). Take out "The Gift" too and it drops to just +0.4% for Fall 1997. What does that mean? The boost was Scorpion, not Seven
. And if not for Scorpion, the fall block of Season 4 severely underperformed the average of all fall blocks (when I mean fall blocks, I mean the episodes airing through November or early Dec). Some may argue Seven prevented a bigger ratings plunge and she may very well have, but the plunge in Winter 1998 is so bad (and followed up by a down Spring 98 too), that would suggest otherwise.
[I gotta post all the ratings data & analysis for Star Trek series and other shows sometime]
For context, the only times Voyager's ratings grew block over block were Fall 1996, Fall 1997, Fall 1998, Winter 1999, Fall 2000, Spring 2001. Both Voyager & DS9 had a problem with their ratings in spring.
And I'm not sure what's behind Winter 1998's drop. It looks bigger than competition with the Winter Olympics at Nagano and the loss of the Milwaukee market (anyone watching Voyager in the Milwaukee area probably remembers that time) would suggest.
Voyager was UPN's top-rated show til 1999 and 2nd highest rated show thru 2001. WWF SmackDown! was the highest rated show in Voyager's last 2 seasons but Voyager still led among all real scripted dramas & sitcoms. And it was no contest. The next series was a distant 2nd or 3rd. They would have been foolish to deep six their flagship series.