While I'm closer in opinion with Mekkkah's in the sense that, no matter what we think of it, FEH is still a gacha in essence and no matter how much appeal and flair the game has to me, it's still what it is.
But I do play the game though, and had since it launched and stuck with it because... the game is F2P friendly. My fear with Heroes at the start was that it would gradually push harder on the player to spend money, and that would eventually cause for me to quit it, but pretty much the opposite happened.
I don't think there has been a higher incentive on spending money since launch (other than more characters being added into the game, but that isn't in itself a money making scheme when you would expect that out of any other videogame like it) and the game also... just... rewards you with a lot of free orbs. Constantly. They even add more features and game modes that ALSO reward you with orbs, and what's more, you can definitely play the game without spending a single cent because... that's what I've been doing, and know a lot of other people who play the game that way.
While I think there's definitely a discussion to be had regarding gambling and it's relationship with the "loot box" model in videogames, I don't feel like Heroes is a competent center for the discussion due to how, again, F2P friendly it is (especially considering how lately Nintendo has been making business decisions that make you wonder if they really want your money) so while I wouldn't recommend the game to someone I know has a spending addiction, I would recommend it to anyone else who would ask me for a mobile game recommendation.
(I feel like I made a very small point but whatever)