Impressive that real Doctor Who fans are all agreement about when the show was enjoyable -- or is it that being agreement about when the show was enjoyable is what qualifies one as a real Doctor Who fan?
Let us think about this.
The Classic series and Eccleston/Tennant/MSmith/Capaldi had higher ratings and higher Appreciation Index scores for the overwhelming majority of episodes than the garbage that was post Capaldi/Moffat. That includes higher ratings for Anniversary Specials and Christmas Specials (Of Course Chibnall replaced Christmas specials with Holiday Specials -Ugh). (That also includes ratings for BBC America, until ratings declined during the Chibnall/JW era). Disney apparently didn't think the ratings were good enough for the RTD 2 era, since they decided not to renew.
Sales for Videos, Books, Magazines, Action Figures, etc were also much higher during the the Classic series and Eccleston/Tennant/MSmith/Capaldi years
than post Capaldi/Moffet
During the wilderness years (1990-2004) it was the fans who kept the show's future alive by attending conventions, purchasing books, videos and audio adventures featuring all 7 Doctors from the classic series and the 8th Doctor. They also purchased action figures, magazines, other merchandise and many created fan films.
It is logical to assert that they are true fans, and they certainly were fans of the classic series.
When Doctor Who returned in 2005, their was great celebration, and people were overwhelmingly supportive of the new series for the Eccleston/Tennant/MSmith/Capaldi years. Then Chibnall became showrunner, decided on a false origin story, had no respect for canon, inserted identity politics and hired incompetent production personnel who had no/or limited sci-fi experience. Sadly, RTD 2 continued the downward spiral.
Now, there is no new series planned for production, merchandise sales are plummeting (what little there is features Tom Baker, David Tennant, Matt Smith and Daleks), no new streaming partner has emerged (the Disney fiasco is quite probably the reason), a planned Christmas special that has no starting date for production,
and any continuity is in complete disarray.
So yes, fans of the classic series who supported the show during the wilderness years are the reason that there was an audience for the show's return,
and those fans also supported the show through the Eccleston/Tennant/MSmith/Capaldi years. They have clearly rejected the farce that is Doctor Who in name only post Capaldi/Moffett