No, I don't think so. "Happiness" is a delusion in this reality, it's truly irrational to be happy in this cruel, harmful world. And anyway I think that many people continue existing as suicide isn't straightforward, this existence is all that they know or they are staying here for the sake of others, it doesn't mean that they are "happy", as you hear of people being stressed and complaining, I don't really believe that humans are ever really satisfied anyway, as life as a concept is focused on the fulfilment of needs, and if a need isn't met then this will just lead to more suffering.
And often trying to fulfil needs is tiresome, a struggle and a chore, even if there isn't any extreme suffering existing is still dissatisfying, and anyway the average life consists of being a wage slave just to decay from old age and end up in a nursing home, it's just pointless and meaningless suffering really.
And I think that if people were truly "happy", then why would people resort to coping mechanisms to relieve them of the emptiness of their existence. But anyway I personally don't understand the appeal of existing, I just find it tiring and unnecessary being awake and I always feel so much dread when I think about the future, as there is no limit as to how much one can suffer. Existing is just a burden in general.