See my post above. There may be "super-traders" that successfully play such complicated short-term trading strategies, and they may take money from less sophisticated traders; but, averaged over all traders, short-term trading will always be a losing game.
I'm curious what you think of poker and how it compares to the argument you are making.
I don't play poker, but it seems to be a good analogy. Some players may fare consistently better than others on average, by their greater skills at psychological manipulation and play strategies; averaged over all players, however, it is obviously a zero-sum game.
However, in day trading there are thousands of players who do not know each other. There there seems to be less room for successful psychological manipulation in that case.
Most winning in poker comes from good playing strategies. Psychological manipulation isn't as much of a factor as your average layman might think, because you often won't know anyone at the table you're playing at (unless you play pretty damn high stakes or constantly play), and there are a number of successful players who outright ignore it. Most of the psychological aspect involves a lot of guesswork, because for 999/1000 players you play against, you won't ever get to know them well enough to really know exactly how they play.
What's important is that you're playing with players worse than you, and I've got to tell you, if there is a better "table" to sit at then the cryptocurrency markets, I'm not aware of it.
That being said, I would agree that actual day-trading is probably going to be pretty much gambling for most, as short time frames seem to be a lot of noise in such a small market, but mid or long-term trading seems fine.
So yeah, the analogy is pretty apt, I'd say, but it goes a lot deeper than "negative-sum game, best not to play if your goal is profit."