I don't think trading is a job. Because for me real job is where you can make money daily from your hard work and effort. But trading is different, there's no guarantee that you can always make money, and you must always used capital for every trade and aside from that there's a risk of losing it. So for me, it's better to say trading is a business because it always has a risk same with trading. Despite of that, if the trader is not profitable and keep losing funds because they trade out of nowhere from the chart then it's called gambling, not a business.
I respect your opinion but I don't understand why you mean only manual labor by work. See workers earn money through their physical labor it is work just like a businessman earns money by performing business activities and sometimes incurs loss this is also work and those who do official work at institutional level also include work. But in any case everyone in the world earns their livelihood through work from their respective positions so no one is unemployed.