Yes, but in the end, there is no real motivation to respond accurately to surveys either. It's just that it's our reflex based on our previous social interactions that it feels wrong to respond inaccurately. Similarly, it will feel wrong when responding in a socially unfavourable way to a question about well-being, even if it's a survey.

Additionally, longer-term happiness is a quite vague experience so there isn't much keeping one from interpreting it however you like.

Of course, I'm not saying that there is no truth to the report. I'm just saying it's not particularly newsworthy because the numbers aren't particularly concrete and it doesn't describe any single important event at all.