Your intentional aversion to the full context doesn't help anyone understand the situation.
When people do not understand any context, they are lead to believe the situation is absurd and is occurring for no reason at all.
Full context allows the public to have a sense of things.
Here is an honest attempt building a storey via several separate but related facts:
(1) In the 1800s, Europe had essentially lost a tradewar with China. The Chinese economy was somewhat of a marvel of the 1700s-1800s, studied by US presidents and founding fathers like Ben Franklin even.
(2) The UK couldn't produce anything the Chinese wanted to buy (a goal to help the UK economy), but ultimately hatched a plan to smuggle a well-known deadly and addictive drug into Chinese ports: Opium, which has been known to grow well in the India colony / Afghanistan and is also related to heroine / morphine / opioids.
(3) The UK's drug smuggling cartel via the British East India Company and backed by their navy eventually causes huge problems for Chinese citizens and their every day life. People are dieing. The Chinese government then organizes special anti-drug smuggling operations to end the illegal drug cartel's drug smuggling.
(4) War starts. The Opium Wars. Plural. The UK navy steps in, the Chinese military was defeated, and this was all to force the Chinese to permit the UK drug cartels to continue operating. Part of the treaty ending one of these Opium wars allows Hong Kong to be leased to the UK for them to set up an offensive post on Chinese territory from which to continue poisoning the Chinese public.
(5) HKs economic miracle was propped up by drug smuggling and money laundering and tax haven status. It wasn't much of a miracle. Drug smuggling and tax dodging are universally condemned both in the West and China.
(6) The public in HK is losing features of Western civilization (like a free press and anti-beijing school programs) as they transition back to governance by the broader Chinese civilization.
(7) There IS a small degree of turmoil as HK society is re-organized, but it should be understood in context. Transition from Civ A to Civ B, who both have completely different systems of law.