Lord of the memes

Yup. Basically:

Ring: I can make you into a great warrior. Like the old Elvish lords who commanded great armies!

Sam: That's absurd, I'm obviously not cut out for that lmao

Ring: Uhhh...oh I got one. You see that mountain? You could turn all of that into a beautiful garden, and the land around can be beautiful meadows. You'd be the greatest gardener ever!

Sam: I can't manage a garden that large on my own, I'd need a whole army of gardeners doing the work for me. And if people are gardening for me, that's no fun. Thank you kindly, Mr One Ring, Sir, but I don't think I'll be needing your services. My little garden is good enough for little old Sam.

Ring: I can't fucking deal with this guy, I give up.

Yeah yeah. Replace "the one Ring" with "a potayto" and see again how Sam is selfless and nice.

It's one of the things I hated about the movies. Sam has a little Dutch angle moment, weighing whether to give back the ring with lots of facial expression acting.

It's been a while since I read the books, but I don't recall him really thinking to much about it. He just gives it back to Frodo, and as a reader, you're left wondering whether the ring just didn't have enough time to grab hold, or maybe Sam is just truly pure of heart.

Then you remember that Smeagol killed someone over the ring immediately. Sam is just that good of a guy. Better than Frodo, better than Bilbo, better than Galadriel, and even better than Gandalf.

The way I interpreted Tolkien’s answer was more that Sam was the classical hero in the sense that once he returned home, he got a happy ending with Rose. Frodo on the other hand was irreversibly wounded and did not have a hero's ending, having to leave to his beloved Shire to heal in Valinor.

He did not claim that Sam's story was more heroic in the sense most people would associate with the word.