Neither of those is 'laughable', even if somewhat inaccurate. The biggest piece of this inaccuracy comes from the fact that it is not known what % of these are from the total, i.e. absolute value numbers are hard to be derived. But nobody is claiming (nor aiming at) the opposite. This whole conversation is about
trends. It has nothing to do with the size of the observed data, only with how representative it is. It probably isn't very much, on any given level. But you take a look at one graph here, another there, some Steam charts and... the puzzle pieces start to overlap, actually. Any company can decide what info to share and what not, but some things really can't stay hidden.
It is often said here that (for example) few people use GLLF and therefore it is not a representative measure. There is no such rule. It is not accurate for total amounts and probably differing among the servers, that's for sure. Whether it is representative or not is arguable. But it doesn't have to be extremely representative. Again, this is not about accuracy or ultimate data completeness.
I'm deviating from what I wanted to tell you...
As mentioned above, if the point is 'Have fun' - you have a valid argument. Suggesting to the people interested in the game to ignore 'some graphs' and just play for as long as they like it - you have a valid argument. Yes, it would be a bit of a useless effort because people's opinion will never result from seeing some graphs anyway, but still you are on a safe ground.
Starting to play by the 'graph rules' - willingly and, say, in full conscious

- and trying to put an opposite meaning to the information there is where you loose the ground. And I don't see a reason for you to push in this direction - you have another, very valid, point.
I know for myself that my opinion on the game and the choice to play it or not have zero to do with some graphs. I have to be ######## [OK, should I say 'silly' or something...] in order to allow graphs, forum threads and official reviews to form my opinion on a game (or a book, movie, etc.). The opinion is formed by other means (mostly actual play) and the decision to play or not is the result of that opinion. As are those graphs. They are the result, that's the whole point here.
Now, I know you are not claiming otherwsie, sorry if this sounds as if I'm 'teaching and preaching' (gosh I don't want to sound like that other forum user). It is only to suggest you that you'll be better off sticking to the good logic of 'Simply have fun, guys'. This is never wrong and you yourself should ride the tide full speed as long as you like the game. Honestly, don't go into numbers and trends because you won't like it, with a tendency to get scared. Suffice to say that those who should be scared are already scared or at least I hope they are, so that they can make some changes.