No one where I live and use metric system even have clue what is the feet and inches mess... Like five foot what? Why not do it properly and say five point something feet like sane systems.

At least here in Western (continental) Europe, it really isn't. I have never heard somebody say something like "She is almost 6 feet tall".

Okay so how would they describe someone's height?

For example, telling a story about their daughter who has grown quickly and is now "almost [n units] tall"? Are you saying they would use centimeters and expect their listener to know what "184 cm" looks like?

I'm not saying metric people use "5 foot 9", but it's common in my country (Australia) at least to use "6 foot" because that's a nice easy rounded benchmark. In metric height, there is no benchmark until 2 metres tall, which is a rare height even for men.

People would either use 10s of centimetres, so saying "my daughter is almost 170cm tall" or use a measure relative to somebody else, often including "heads" or "half-heads" ("my daughter is already half a head taller than me"). You might want to argue that a "head" is pretty similar to a foot though.