Social media and other addictive Internet sites - people are constantly glued to them, even on their work, which decreases their productivity. Social media also cause depression in many people, because they not only procrastinate, but also constantly compare their life to others, which leads to dissatisfaction. Also social media are good at spreading lies and fakes, which can have negative effects on the economy - anti-vax panic, anti-GMO, political manipulation and so on.
Talking on social media vices, understandable they are not but that is not saying that there are no good side to social media that has also helped the economy and, it is also helping it. For example, information about government policies, employment chances are being disseminated through social media and handles so many times.
More too is that awareness of how to make money on the internet comes from social media most of the time. Like cryptocurrency trading, forex and commodities etc. Those can help individuals and cause a growth in the country's economy.