There are all kind of traders, function account size, of who's money they're trading, of their understanding of markets' working, etc.. There isn't a "one size fits all'. What you called "savvy traders" are those who make money from commissions ...
Care to expand? There are plenty of non-MM players that have strategies across the time-frame spectrum as well as across a range of instruments. That does not mean they collect commissions.
Is long-term value investing more profitable than shorter-term trading? It seems to have been for some in 2017. Will it be in 2018? Who knows? The question asked can be answered in two ways depending on whether it is referring to individuals, or investors and traders in aggregate. Short term trading for particular individuals at particular times will always be more profitable then long-term value investing over similar time periods. Your job is to look forward in time and determine whether you are one of the particular individuals.
Assuming you're as good a trader as you are an investor, shorter term trading is more profitable due to compounding. As others have stated, you can be both at the same time if you know how to trade across a range of time-frames.