My understanding of this specific tax , is its for specific...

My understanding of this specific tax , is its for specific markets , such as foreign exchange and or shares and or say oil futures or the like.
The idea behind it is to produce less volatility.
To use this " sledgehammer " to crack a nut , may IMO be overkill to the max.

I find it interesting that bill gates has followed my idol , john galbraith;

https://www.forbes.com/sites/timworstall/2014/03/18/bill-gates-points-to-the-best-tax-system-the-progressive-consumption-tax/#2196099d2fc9

Raider