For those intererested, here is some reliable info on the “Shugden” issue. This does appear on a DL website, but is written by Georges Dreyfus, a very sensible and reliable scholar.
For those with less time: there is a Tibetan protector deity named Shugden, who has some historical associations with sectarianism in Tibet. The DL feels like this deity is not an authentic Buddhist deity, and says that his followers should not worship him. For a religious figure to say “this practice is inauthentic” or “this practice is authentic” is normative within any religious tradition. The narrative of some Tibetan and many Western followers of Shugden is “the DL is trampling on our religious freedom and banning our beliefs / practices.” You will notice such posts immediately crop up on blogs / discussion / news related to the DL.
One of the important promoters of Shugden in the West is Geshe Kelsang Gyatso. His organization “the New Kadampa” can be found in many urban areas in the U.S. (and for those not in the know about all these politics, it would be difficult to see their association with Shugden). Many of these followers promote the “oppressive destroyer of freedom DL” narrative.