Here's the flaw in your analysis, BourneIdentity: someone who was an active JW in the 1960's (like me) could say, "I truly could say the meetings were so encouraging and that I felt the Holy Spirit present and operating on all of us, but not so much after 1975."
Likewise, someone who was an Earnest Bible Student in Germany in 1925 could look back longingly to the guidance of Pastor Russell prior to his death and say, "I truly could say the meetings were so encouraging and that I felt the Holy Spirit present and operating on all of us, but not so much after 1918." If you were to read the book by the Sadlack brothers from Germany titled "The Desolation of the Sanctuary" this was exactly how many Bible Students felt about the leadership of "Judge" Rutherford. The book is still available today in English fro LULU.com.
I'd be willing to bet a nickel right now that JWs in 2050 will look back longingly to 2025, when the Watchtower meetings were so encouraging and so evidently filled with Holy Spirit.