Buddhism is having a massive resurgence in China (+ Taiwan, HK, Macau).
From the reports I heard, its Christianity that is soaring in China and Taiwan. Maybe both are increasing at the same time or one of the party is making false report.
According to the CIA fact book, Taiwan Christian population = 4.5%; and for the PRoC = 3-4%.
These figures are barely "soaring".
Buddhism on the other hand, Taiwan Buddhist / Daoist = 93%; PRoC has no figure, but it is obviously far, far more than Christianity. I've heard reliable figures of around 20-40%.
For example, in Taiwan or the PRoC, Christmas is not a holiday, and barely an event at all.
For Taiwan and HK, Vesak Day is a holiday.
Perhaps it is reading Western media, which often has a vested interested in indicating that Christianity is popular (anywhere)?