while the WT told the truth about the pagan origin of holidays, they did not tell the truth about how Christian should view things as pagan. Just because it is "pagan" does not mean it is bad to participate in. The origin or how and why people celebrated days in the past has nothing to do with how and why they do it today. For instance at one time there may have been mother worship but no one observing mothers day today is actually worshiping their mother. They are simply showing her honor and this is scriptural.
You cannot remove all things pagan from society. If you wanted to try you could not use our calender for the days of the week and names of months are pagan. Also many JWs wear wedding rings and that is pagan also. The thing that changed when Christ came is that it was "in your heart" what mattered and nothing more. If you knew you were celebrating days for the enjoyment of being with family or honoring your parents and not for worshiping false Gods as you kept your heart pure, you could celebrate any day you wished.
The Apostle Paul makes this clear in Romans 14 starting in verse 5 that these are conscience matters. So I will have to disagree at least partly with your statement that the WT had the proper view of holidays.
Also, it depends on how you define truth. They have some teachings in common with other Christian denominations but much of it if you check the record and go back to accounts of historical Christianity and what Jesus and the Apostles actually taught, you will see that the WT is guilty most of the time of deveating from what is simple in the scripture. But to them that is truth, truth is subjective. Is it their truth we are talking about or the truth as most Christians believe? Lilly