The recent sniper nerfs have come after a lot of community complaints. Here are a few thoughts for the devs about the risks of balancing based on complaints, and even on data collected server-side.
People who play sniper are a self-selecting group: assuming the player has half a brain (which, granted, is not always the case), he will only continue to play sniper if he is effective with them. Therefore, as snipers are nerfed, fewer players will play them.
It then follows that the average skill level of those who continue to play sniper effectively goes up after every nerf, since it takes more skill to be effective with a less effective weapon.
Based on this dynamic in which snipers are self-selecting, how effective snipers are seen to be does not depend purely on how strong the weapons are. In fact, you'd expect the average effectiveness to remain relatively constant as people who are less good at sniping move onto other classes.
This means that how strong snipers are perceived to be by those who do not play them will not be much affected by the nerfs. Indeed, this is exactly what we are seeing in the community responses that claim "the sniper nerfs are not enough." What those responses do not see is the process of self-selection.
In fact, the calls for nerfs to snipers (not just in the latest patch, but really for a long time) have not much to do with how effective the weapons are at all. Remember when jump sniping was removed? It was surely not because people were getting repeatedly killed by jump sniping. Instead, it was because people didn't feel like there was a counter to it on the rare occasions on which it happened.
The proof that the calls for sniper nerfs do not have much to do with weapon damage is simply in the fact that snipers have simultaneously been seen as overpowered and ineffective (see the bottom-scoring Vas tropes). The complaints do not have a quantitative basis, but are instead qualitative.
This is compounded by the fact that the best counters to sniping does not lie in obvious game mechanics (though those do exist, and Javelin is only the latest), but rather in "soft" counters like teamwork, map knowledge, and game sense. At a basic level, the design of the maps themselves provide counters.
Given that the complaints about snipers are not in fact based on the damage of the weapons, I think the recent nerfs to sniper damage are a mistake. They will do little to stem the tide of complaints (previous nerfs didn't and there's little reason to believe this one will be any different) and will only further exacerbate the gap between infuriatingly good snipers and infuriatingly bad ones. Further, the nerfs have the effect of making certain playstyles non-viable, like the kind of high-risk-high-reward aggressive sniper play. (Of course, this will only increase the prevalence of snipers who just sit back, and increase the frustration of those who are unable to counter them.)
Instead of hard damage nerfs to bodyshots, which isn't far from a sledgehammer approach to balancing, more precisely targeted changes are needed. Greater damage falloff, for instance, would reduce the frustration of being hit for almost full-health by a bodyshot at range, while preserving the reward for hitting a close-range shot on a fast-moving target. It would make cheesy plays less effective while keeping open a diverse set of playstyles.
Ultimately, the ideal would be for players to be more aware of the tools they have to counter snipers (other than spraying an SMG at long range and hoping for the best). Just to throw an idea out there, post-death tips could be used to give recently killed players ideas about counters to what just killed them (of course, this applies to not just snipers). This would be a way of teaching newer players by letting them know the mechanics available to solve the problems they are facing.