@kestrel This is my favorite topic. Let's debate it more!
An underlying theme in all of Lord of the Rings - to the point of it being explicitly brought up on multiple occasions by Gandalf and Galadriel - is that the fight between good and evil isn't really determined by mighty warriors but by everyday people stepping up in whatever capacity they have to defend their friends and communities.
It's for that reason that Sauron isn't defeated in some final showdown against Aragorn or Gandalf. In fact in the movies they debated that (and shot the scene, it's on youtube!) but then - correctly - realized it was unthematic. The hobbits are the true heroes; it was these complete nobodies' journey, hardships and sacrifice that brought down the Enemy.
Sam embodies all of this. He was no prophesized figure. He didn't come from a storied lineage. He didn't inherit a Ring of Power. The dude was into landscaping, he dug holes in the dirt for a living in a backwater village his whole life.
Sam, also, by the end of the story carried the fate of Middle Earth solely on his shoulders. He fended off the most corruptive power in existence that brought down Numenorian Kings and was feared by Maia and Noldor Elf Queens for its seductive properties to help his friend. He fought ancient spidery horrors in freakin' Mordor. The dude was hardcore. He was also a fucking gardener.
And at the end of it all he went back to gardening. What a madlad. Like... Grey Havens? Going to Valinor? Living like a goddamn hero in Gondor? Nah, he just planted trees, raised a family and, you know, had a good life until he passed away from old age.
I don't think it's even close who the hero in this tale was.