With the increasing number of sophisticated Automated Trading Systems ATS also known as "trading bots" - which are fully automated 24/7 algorithmic computer programs - out there, I would say day trading is more of skill than luck. Because these bots were designed to "improve on the human skill set", and not built on luck.
Yes if someone is using that then it is more better than the skills. But it is a different type of trade which we cannot compare with human mind trading. while if we compare the trading in human mind then it is more risk to do day trade. For them long term investment will be more higher benefited as all of the coins go higher in value in long term.