Is eliminating all human emotional suffering possible? I think that that is an interesting question to ponder.
There are proposals about how to potentially stop aging. Radical life extension technologies is a term that can be used for technologies that may effectively stop and/or reverse human aging. The SENS (Strategies for Engineered Negligible Senescence) Research Foundation (SENSRF) is one organization attempting to stop human aging. The giant business, Google, has even launched a company, Calico (California Life Company) which will seemingly attempt to do similar things as SENSRF. Even if these efforts are successful, humans will not be immortal on Earth; physical trauma or cessation of anti-aging treatments will still lead to death. Radical life extension technologies will not eliminate death, but they may greatly reduce the amount of death that occurs.
It seems that when considering the nature of unpleasant and distressing negative emotions, a great deal of personal responsibility might be needed to experience minimal amounts of negative emotions and maximal amounts of positive emotions.
Additionally, it seems undesirable to be unable to experience negative and undesirable emotions. It might actually be dangerous. Unpleasant emotions can potentially be useful.
Developing effective emotional regulation skills is possible. It seems that, in theory, if all humans are able to possess effective emotional regulation skills, then all humans might be able to experience minimal amounts of unpleasant and undesirable emotions.
Just as developing radical life extension technologies might be possible through technology (the book Ending Aging: The Rejuvenation Breakthroughs That Could Reverse Human Aging in Our Lifetime describes how it might be achieved), it might be possible to for humans to experience nearly unimaginable amounts of subjective well-being and nearly unimaginably infrequent amounts of unpleasant and undesirable emotions.
Social relations may have to change in order for humans to experience minimal amounts of emotional distress. All social relations are created through individual personal decisions. Take crime as an example. Humans break laws and engage in crime for reasons. If crimes can contribute to emotional suffering, then society must be structured in such a way as remove from existence as many reasons for engaging in crimes as possible.
If it is possible to stop all human emotional suffering, then it seems that it must most likely involve somehow transcending the human condition and human nature. This may be impossible or undesirable. However, reducing the amount of human suffering on Earth to nearly unimaginably low levels may be possible through societal change and the acceptance and embrace of personal responsibility (for attempting to regulate one’s own emotions) on a nearly unimaginably massive scale.