The problem is that for all the loyalty a small, experienced community gives, pandering to a large mob of users will sell more copies of the game in the end for the majority of games (especially CoD). A lot of publishers just care about the money (and often pressure the devs to do the same), having a game that satisfies a small percentage of the player base is not usually a priority for them.
I don't agree with this philosophy at all. At least from a gameplay perspective. I think a balanced game will sell more and continue to sell more in the long run. In fact, i don't think balancing at the top causes any problems for the casuals at the bottom. (edit: and isn't this what Overwatch is doing?)
Let's take Destiny as an example. If Bungie took the 100 best players in that game and balanced it out accordingly the entire experience for everybody would be better. Much better. How would your average gamer or the entire casual mob be affected by this in a negative way? All i see from people on Destiny are cries of horror about the balancing issues that game constantly faces.
So, yeah I don't see it. Most of the casual player base play the game other than for high level skilled play, right? They don't notice things anyways. They just play, for many other reasons, like leveling up, or cosmetic unlockables, or PVE, etc. Look at how long it takes your general population in Titanfall to notice that something is OP or completely broken. I've noticed it's taken at least a month or more after a few people start posting threads up on reddit.
Now, this is not to say the barrier to entry should be ridiculously high, now that can push people away. I'm saying the game should be balanced at the highest level in order for there to be a natural progression upwards - the more you play, the more skill you attain, the better you become compared to the rest of the community. And this progression should never stop.
When you balance the game for the population as a whole, taking into account the mediocre to the average, it only opens the game up to frustration and not just for good players, but for everybody. Why? Because good players discover the garbage faster, the middle tier players follow suit, and before you know it OP crap/tactics are being abused to the detriment of everybody.
If you don't see it like this, or understand it, i'd like to know why.