Hanging poor smugglers for weed delivery is pretty inhuman imo. Not sure where you get your sense of proportionate punishment from.

I don't agree with their laws, but they are rather simple and comparatively effective, though ruthless and as you say disproportionate.

As someone who has spent time in that 'city-state' I can confirm that not being east asian will make you a target in the eyes of the majority who have vilified foreigners as job-stealing parasites while the multinationals they work for try everything to hire locals and hire the foreigners as last resort. This then makes sure there are multiple cameras ready to capture you breaking any law, local people trying to test you by shouting in public or pushing you in the way knowing full well that any opposition will be documented, colored as entitled aggression and will be used to mount public pressure to make an example out of you. Source below of what happened to a white women, just add biases against south and south east asian men to the mix and I can tell you the image of singapore projected will not match what people feel when they live there. https://archive.ph/tEwTp

The president of Singapore,Tharman Shanmugaratnam, is literally a man of south asian decent. He won the election with an overwhelming majority, 70%, the most ever.

https://en.wikipedia.org/wiki/Tharman_Shanmugaratnam

Barack Obama was the president of USA, did that fix all racism in USA? These are all arguments in bad faith.

The idea is not to agree with the law or that the law is good or even essential but by having few of them you avoid the misery and achieve better compliance.