1949 through to about 1970 whilst there was no formal economic policy, there emphatically was subsidy. The administration was providing social housing for those refugees, education for their children, infrastructure programs that were often more ambitious than in the UK - providing complete new industrial towns, and land reclamation. There was a policy to limit cost of living increases as far as possible as the fledgling industry relied on low labour cost to compete.
There were also export restrictions on textiles and clothes - the backbone of the HK economy up until the seventies, perhaps longer. Those restrictions were certainly in place with the UK and Europe, not sure about the wider world.
The large subsidy during development merely wasn't direct to industry. Yet with textiles and cheap plastics, the two industries that formed the bulk of HK's exports, they happened to be two with low startup capital costs. As a result the HK economy was heavily skewed toward small and medium businesses and low startup costs.
She also had the unique position of the free-port whilst being allowed better access to China than the rest of the globe had. Those refugees were the reason she grew, as they were mostly highly educated and skilled anti-Communists fleeing China's civil war, and the ugly repressive aftermath. The doctors, bankers, merchants and financiers rushing in surged the population from a minor town supporting the port and little else, to major offshore centre.