It's gambling, but worse in almost every way.

In online poker, you don't often get big fish at the micro-stakes--it's not worth their time and there are table limits. In DFS, you can create an algorithm that sets your lineup across all the betting arenas.

There's also a larger informational asymmetry - in poker, there are odds and betting styles to keep track of. In fantasy, there are poorly priced players (so not only do you have to predict the expected value of the points, but you have to compare that vs. the price), last-minute info (many daily players don't know that you can reset your lineup on some sites), and statistics on nearly everything (effectiveness of certain stacks, weather, dome/not, turf/grass, home/away, etc) that minds can't calculate as well as a computer algorithm can.

Daily has turned fantasy, which is premised off of an enjoyment of football into a giant scam, with worse odds than a slot machine or lottery tickets for the average joe. It relies heavily on megalithic advertising budgets aimed at the bro who thinks he knows a lot about football because he did well in his fantasy league (and that guy probably does know a lot, but he's woefully unaware of how little his knowledge is compared to the algorithm's).

I play daily for fun against friends (knowing that we're going to lose the rake so we're essentially paying for the software), but you'll never find me wasting my money in tournament play. I think it's embarrassing for ESPN to partner with someone who is (in my opinion) muddying a good deal of fantasy advice out there with weekly bang-for-buck suggestions (which doesn't even come close to narrowing the informational gap, and is just paid-advertising in disguise).