Is Marvel's Thanos actually good?

Luna (No)

Thanos has a huge messiah complex and believes himself to be the ultimate savior. His actions are motivated by a desire to 'save the universe.' And he thinks he is the only one with a good enough idea to protect the universe’s resources for years to come. While this goal sounds altruistic, his methods of executing his 'dream' are harmful to everyone. 

Considering himself to be some sort of a God, he devalues his fellow citizens and looks down upon his own family--believing he's the only good, worthy person in the universe, unmatchable in terms of strength or wit. 

Thanos also doesn't seem to engage in diplomacy or peaceful communication to attain his goal. Instead of explaining his ideas and seeking joint resolutions, he chooses violence, destruction and causes pain to countless families all over the universe. 

Further, he tries to meet his goals through toxic means, which cross multiple moral, ethical, and legal boundaries. He tortures his own daughter Nebula throughout her life without an ounce of regret, and he literally uses his daughters as soldiers, training them to fight for his dangerous cause. 

Ironically, he doesn't think twice before killing the very people he is trying to save. He slaughters entire kingdoms (Thor's Asgard) for power and status. He convinces forces to turn on their own and inadvertently fight for the destruction of half of the universe. His 'army' is comprised of evil people doing evil things, completely negating any good intentions. 

Knowing everything he does and how he goes about doing it, it's clear that Thanos is no good guy.  

Ellery (Yes)

The danger of overpopulation has been widely recognized for more than two centuries. The global population only continues to surge, and with Earth's limited resources, it's a very dangerous problem. 

With this in mind, Thanos begins to look reasonably selfless: he had watched his own species die out due to overpopulation and wished only to protect the rest of the universe from that fate. Further, his 'snap' isn't painful; it simply erases people from existence--and even saves them from any future death and suffering. Additionally, Thanos' eliminating of lives is also wholly random--he doesn't stoop to take out his enemies. 

Central to the exploration of Thanos' morality is the question: if the population is growing so fast, would killing half the world actually change anything? The MCU itself argues that yes, it would, with multiple characters commenting on the improved quality of life. 

Culling the natural population also promotes biodiversity, as human activity is responsible for the approximately 25% of plants and animals on the planet that are on the brink of extinction. Reducing the number of people by half might do the Earth a “huge favor.' 

And it would help human populations too. The black death wiped out nearly a third of the global population, with survivors' wages and quality of life soaring in the years after. 

Modern population growth is actually approaching a relatively stable plateau; it's just one far too high to be sustainable. Thanos' solution would fix that, preserving our scientific advancements while reducing the number of people consuming natural resources. 

Of course, there is no way to measure human suffering, but the facts do point to Thanos having his priorities on the side of good.