The way they used to validate 90 nm scanner was a totally failure,
I read somewhere that SMEE 90nm used many foreign components, including Gigaphoton as light source.
We don't know why it was dead on arrival, we can assume prototype didn't work and didn't reach targeted specs. But anyhow in the past SMEE used many foreign suppliers. Their new machines are 100% localized (and now they are also on entity list, just to be sure they don't change their mind).
My impression is that in the past they were left more or less alone in their development, yes they were granted funds, but that's all. Today they and their key suppliers have strong engeneering support from Huawei, ICRD and many national research institutes. China realized (a bit late IMO) that lithography machine development requires a nation level effort.