If the UK had thought this through, they would have setup real democracy in Hong Kong a generation before the lease ended, instead of doing the colonial "high commissioner" thing. A legitimate Hong Kong government would have survived a lot longer with their people's support.
One could argue in the opposite direction: a real democracy would have been (and still is) an extreme threat to the CCP (Chinese Communist Party) which is an anti-democratic cadre party in the Leninist tradition, and has explicitly stated that it wants to remain one for all eternity. One of the narratives of justification that the CCP uses is that Chinese people neither want nor need democracy.
A democratic HK would squarely falsify this claim.
Indeed, I'd argue that the single most urgent reason (but not the only one) for China 's bullying of Taiwan is precisely this, Taiwan is a thriving democratic and Chinese society.
Chris Patten tried to introduce democracy in 1992, with less than 5 years to go before the agreed handover, and that angered Beijing yes. And then, when the handover happened, Beijing reversed Patten's reforms.
But if the UK had done the same thing in 1980 or 1970 or 1960 or 1950? I don't think the PRC could have done anything about it.
The UK never really cared about Hong Kong democracy. If they had, they would have implemented democratic reforms decades ago, instead of leaving it until the very last minute.
Not to put too fine a point on it, but the British (colonial historically and more recently) have always seemed to find democracy a bit... inconvenient.
If the UK had thought this through, they would have setup real democracy in Hong Kong a generation before the lease ended, instead of doing the colonial "high commissioner" thing. A legitimate Hong Kong government would have survived a lot longer with their people's support.