One of my best customers is in Singapore and I've worked a lot around the Far East between 2000 and 2010.

The myth about Singapore is the duty free point.

Yes technically they have got rid of import duty as they don't charge the WTO tariffs.

However they have a 7% Goods and Services Tax and that is levied on almost all imports. There are some exceptions, such as imports in to designated free trade zones, but those are warehousing or manufacturing areas, so it simplifies say components coming in for manufacturing and then being re-exported, or it delays the GST tax being paid until the goods cross over in to the main customs territory.

That would be akin to us setting up free ports post Brexit, duty free areas where a manufacture could set up, make their goods and export the finished goods without many of the hassles typically involved and only when passing finished goods in to the domestic market, would a tax charge be made.

When it comes to low paid migrant workers, this is common place in South East Asia. In Hong Kong many families had a maid, usually from the Philippines and lots of migrant workers do the menial jobs.

Is it so different over here? We have crop pickers in Lincolnshire as the locals don't want to do it. I've seen several fish processing plants in my current industry, in Fort William, Shetland and one on Benbecula and they all rely on migrant workers because our local workers aren't prepared to work in that cold, smelly environment for £8 per hour.

Whilst it isn't the migrant workers at fault, an effect is that the resident low-paid / low-skilled workers are also affected.
Their standard of living, ability to get a higher rate per hour and/or more working house are affected, because the going rate for these jobs is held back by the almost unlimited supply of labour.

So the whole thing is a bit of a red herring. There are minor differences, mostly cultural, but most developed economies have so far failed to get deal with the issue of the low paid workers in their societies.