I wonder what Bloomberg is trying to prove here. Let's compare
NASDAQ's Forex Market Overview:
The foreign exchange market is the most actively traded market in the world. More than $5 trillion are traded on average every day. By comparison, this volume exceeds global equities trading volumes by 25 times.
It sounds like Bloomberg is making up a reason why Bitcoin wouldn't be money. They could write a similar article about fiat: "only 4% of economic transactions came from merchants".
Personally, I would rather hold my bitcoin that spend it because I am looking forward that soon it can go beyond the $20,000 (or almost) reached in 2017. I am sure that am not alone with this mindset right now.
If that would be the reason to hold on to Bitcoin, traders wouldn't sell it either. But they do buy and sell all the time.
The thing that restricts me in using Bitcoin is the low acceptance, I use Bitcoin to pay whenever I can, but unfortunately that's not very often. Once more merchants accept Bitcoin, I'll use it more often.