Memes

it assumes Chinese imperialism was necessary to defeudalize Tibet

It assumes Chinese Maoists aided Tibetan communists in their overthrow of the brutal theocracy that governed the country to date.

Certainly possible this could have happened another way, in the same way you might argue the US could have revolted against England without the help of France.

But the idea that Chinese integration with Tibet constitutes "imperialism" presumes China's economy is parasitic - leeching resources, robbing land, and press ganging laborers for the benefit of Beijing. None of that is in evidence. Just the contrary. China and Tibet have been engaged in reciprocal mutual aid, to the benefit of both regions.

Most importantly, it doesn’t justify forced sinicization

Capital improvements being reframed as "forced sinicization" is just American agitprop. The Chinese government is extending education as an amenity to a province that lacked it. The Tibetans are learning Mandarin because it benefits them to speak fluently with their wealthy neighbors.

For the same reason Indonesians learn English and Italians learn German, Tibetans are learning Mandarin.