So Destiny 2 on consoles has not even sold half of what the original game sold through physical release. Well clearly that's because it hasn't released on PC yet!!!!!
You have to take into consideration that destiny 1 was on four platforms as well. And people are probably holding off because of the disastrous launch of the first game.
We all know the first game sold down to one single word. Hype. Also I'm clearly just having a fun dig with my original comment as the game has over a million concurrent players right now.
Considering that this didn't include digital downloads, seems about right and what is to be expected even if the game is greater or less than Destiny 1's numbers due to digital purchases rising and physical purchases getting lower and lower.