I think, yes. The answer is it is impossible under current circumstances. China would have to be a different China for democracy to flourish. It's not in the cards any time soon.
If I could just make one point that came up earlier about the early years and about universal suffrage and joint declaration, it should be known that China wanted no mention of elections or future governance in the joint declaration. This is why it remains such a long-term issue. They were taking a snapshot of what Hong Kong was in 1984 and that's what they wanted to continue and figured that governance and institutions would be decided on later in the context of the basic law.
It was Britain who said to China, you cannot get the support of the people in 1984 on the promise that something good will happen four or five years later in the basic law. So they persuaded China to take some language on the subject of democracy or on the subject of future governance and they put forth any number of proposals in that summer of 1984. These were constantly rejected by China. The only reason they got what they got was that the deadline approached in September and the British finally came in with the language and China in desperation took the final version. For that reason it was not well considered, well thought out, or deeply significant language.
To amplify here that what Cradock was referring to in his memoirs was not an agreement to have no democracy by 1997. He was saying that they were not going to get out ahead of what the Chinese were willing to tolerate. But in the context of the basic law, the British did enter the process and did argue vehemently for more directly elected seats to set the bar higher in the years to come. So this is a very complicated history and it gets to your point, which is that it's been iterative since 1984 and it will go on being iterative for some years to come, I fear.