The phrase "All major democratic reforms for Hong Kong were dropped by British Cabinet decision." does not lead to any credible source, only some mentions on a small number of websites or Reddit.

Compare the Google searches:

- "the colonial governors who ran Hong Kong repeatedly sought to introduce popular elections but abandoned those efforts in the face of pressure by Communist Party leaders in Beijing."

  [1] leads to the New York Times article, which I can follow its references.

- "All major democratic reforms for Hong Kong were dropped by British Cabinet decision."

  [2] does not lead to any credible source. In fact, some of the sites appear to be disinformation campaigns (don’t take my words, judge for yourself).

[1]: https://www.google.com/search?q=%22the+colonial+governors+wh...

[2]: https://www.google.com/search?q=%22All+major+democratic+refo...