I also think Hong Kong is going through the same thing, plus I believe China is trying to make Shanghai into its main Finance Center, letting Hong Kong's center fade away.
During the 1990s when there were open questions about HK's status, a lot of the business community (and at least 10% of HKers) immigrated to SG to operate there.
During the 2000s, the PRC made some good faith attempts at assuaging investor sentiment in HK, and that slowed the business and financial services outflow from HK to SG as HK had added linkages to Mainland China that SG would never have.
Now that I can IPO or M&A in China and India with Singapore level valuations, I have no incentive to retain more than a minimal operational presence in Singapore in order to act as a capital funnel to the others.
By 2019, if you were a Chinese company that only intends to operate within China, you had no reason not to move legal and leadership operations to Shanghai.
On the other han, I'd you were a foreign investor, HK de facto become "yet another Chinese territory" which meant it's not a good hedge for an ExChina/China+One strategy which is executed in ASEAN or India, which made Singapore become somewhat attractive.
Basically, the only loser was HK.
That said, this is all business and financial services - no one was actually dedicating serious effort building sustained R&D capacity in either HK or SG when you can hire the people who you would have had to apply PRs (no one who is worth hiring would accept a work visa when they could work for an American company and L1/2 to America) for directly in China, India, and increasingly Vietnam.
Where's the example where you're a Chinese company with most revenue in China (for now) but do sell elsewhere and anyhow, there are lots of reasons to not 100% stick to China,
e.g. gaming companies have moved to Singapore in masses (at least some capacity) due to time and time of gaming crackdowns and censorship
For example, the whole ByteDance/TikTok imbroligo is due to Susquehanna trying to exit it's Chinese investments which are locked within China.
During the 2019-23 period, boards in startups that had Western investors increasingly demanded that either Chinese investors buy them out or that they shift domicile so an alternative path to exit could be found.
Singapore is pretty impressive.
Same can be said about Sri Lanka.