Boromir was the only member of the Fellowship who tried to take the ring. He was vain and entitled, believing that he alone, of the Fellowship, was worthy of the ring. He was a thief and a traitor.
Boromir was a Lord of Gondor, and he wanted everyone to know it. “His garments were rich, his cloak was lined with fur, and he had a collar of silver in which a single white stone was set.”
Boromir did not redeem himself. He failed to protect Merry and Pippin from the orcs, who wouldn’t have found the hobbits wandering alone if it weren’t for Boromir’s actions in the first place.
Boromir would not have felt remorse or apologised if he had succeeded in taking the ring; he only did because he was caught. His image was so important to him that his “heroic” death was staged to create sympathy and goodwill so that he would not be remembered through the ages as a thief and a traitor.
Boromir got what he deserved.
Imagine being the leader and hero of your people, groomed from the day you were born to lead and protect. You’re fighting a losing war against an enemy that will brutally slaughter every Man and child they come across. You are about to lose the last line of defense in Osgiliath and your once great father is quickly losing hope, and his mind.
In a final desperate attempt you ride West to seek aid from an old ally that has set its sight on leaving you behind to an inevitable doom.
Once there, you stumble upon your one and only chance to save your people, but to your dismay the secluded people that you have protected with your people’s blood for centuries refuses to give this weapon. Instead they are sending the weapon with some “children” who have never seen war on a suicide mission that everyone believes will fail.
For weeks on end as you trek through hostile land while an impossibly powerful corrupting force is slowly tearing down your mind, reminding you of your people’s struggles and telling you how it alone can give you the power to save them, and the world.
And then disaster happens and the leader of the suicide mission and the only one who could lead the way dies and you’re left directionless. Finally you break and try to take the weapon needed to save your people.
How are you a bad person in this scenario?
The wisest angel in the world didn’t even dare to touch the object in fear of its corrupting power. The most powerful elf on Middle-Earth earned back her spot in heaven by resisting its influence once. Boromir was the only human in the group, and the one most weary and desperate by the war, the perfect target for the ring.
Boromir was a great man, but unlike the rest of the fellowship he was also human, and with that come flaws. Your characterisation of Boromir is of him under the influence of the one ring, which is unfair. Free of the ring’s influence we see him as a selfless hero willing to give his life to protect the hobbits from harm.
It’s a shame this scene never made it to short edition of the films.
I don’t know the lore too well, but long life and invisibility that the ring bestows on mortals ain’t going win any war.
That ring’s primary domain is domination, with other extra powers given depending on person. In the hands of someone like Gandalf or Galadriel the war would most likely have turned before the ring inevitably betrays them, or they themselves becomes as bad as Sauron.