This has been floated at various points over the last 4 years but my read is that people are happy with how EVUS is working and outside of that trimming validity is a logistical nightmare.

The reason they got a 10 year agreement was not really political but instead due to limited resources on the US processing/interview side.

Not saying it can't be taken away but it would introduce a lot of problems. That aside, Beijing has actually kept their side of the deal and Americans get 10 year visas as well which is convenient if you do business there.