According the to 24 hour volume of the exchanges on the coinmarketcap data the answer to your question is clearly a yes. People were investing and trading like crazy during December months and the low prices we have right now has lower 24 hour volume as well.
The reason the volumes have gone down isn't only because less people are trading, but also because of the 'lower' price.
100,000BTC volume @ $15,000 per coin is $1.5 billion in total.
100,000BTC volume @ $6500 per coin is $650 million total.
As you can see, it's quite a difference while the BTC volumes have remained exactly the same. On top of that, hype volume is never a good indicator because it never lasts long, so technically speaking, the current volumes based on 'genuine' demand are perfectly normal. In other words, it's not low at all, just like how the current price isn't low. We are exactly where we should be right now.