Did the Watchtower Corporation create false doctrines intentionally to enhance the proliferation of their own printed publications ?
No I think the WTS created false doctrines different to mainstream Christianity to give the impression they have a hotline to God.
The paradise earth hope, no cross, no holidays, no blood transfusions were all designed to create the idea that they'd ditched false Christianity and by searching the scriptures and asking for Holy Spirit that were now the chosen of God, the true religion.
The end of the system and the dates were all part of that because the mainstream churches weren't doing it. They were waiting to go to heaven.