Okay, I'm going to play devil's advocate.
A large part of this game is about progression, right? Sure, you can test your prowess in FP/Coli/GW, but those modes are not very time intensive and they also largely depend on gear progression anyway. I can't speak for everyone, obviously, but RPGs usually attract people who enjoy progressing their heroes, watching them grow in power, etc.
In other words, on some level, the grind is an important feature of our enjoyment of DS (this is also why people on S1 and S2 are bored and clamoring for another gear update).
I think we can all agree that there is some level of "progression destruction" that we would not be a fan of. Like, what if instead of having a double drop 3x a week, they simply max promoted/geared a toon 3x a week. You would very quickly run out of heroes who weren't max promoted right? Would anyone have a problem with that? I don't think I would like that approach.
So if we can agree that there is some level of "progression destruction" that is unhealthy for the game, then we can surely agree that different people will view where this level falls differently. If every day was double drops, would that get old? Would it cease to have meaning or be a special occurrence?
I don't know what my level of "progression destruction" is, but 3x double drops each week is approaching it.
I think on some level it removes a bit of the competitive aspect as well. Double drop items used to be meaningful; they used to be rare, something we had to work toward; they used to be special. Offering 3x double drops a weeks removes all of that - double drop items are no longer meaningful, special, or necessary. It bridges the gap between casual players and tryhards. Yes, the tryhards will still have an advantage in other resources ... but that doesn't mean it isn't closing the gap.
I'll be curious to see whether they continue the rate of double drops once O7 is released.