Seeking Understanding About the Severity of Polytheism in Islam

As-salamu alaykum, brothers and sisters. I am a Muslim who believes in the oneness of Allah and that Prophet Muhammad (peace be upon him) is the final messenger. Still, my iman sometimes wavers on certain matters because I try to stay open-minded and not judge others harshly. While I see this as a good trait, I wonder if it also means I might misunderstand some parts of Islam. One thing I struggle with is the idea that all non-Muslims will be punished with hellfire forever. I trust that Allah (SWT) is the most just and merciful judge, so I often leave things in His hands. It’s hard for me to believe that people who do good deeds and avoid harm, but don’t believe in Islam fully, would face eternal punishment. Especially if they were simply misguided or never had the proper chance to understand Islam. For example, today I visited a local seafood shop run by Chinese owners, and I saw an image with some supernatural symbolism-kind of like a good luck charm. I didn’t see this as evil, just different, and I felt curious about their culture. It’s difficult for me to think they would be punished for something that made sense to them and that they were taught since childhood. I try not to overthink this because I know it's not my place to judge others. Yet, I find it confusing when I read verses in the Qur’an about severe punishments for disbelief. Even people who respect Islam and live good lives but don’t accept it fully-while I believe faith in Allah is best-I wonder if their disbelief should be met with such harsh consequences. Am I off track in my thinking? I would really appreciate any advice or insight to help me understand this better. Jazakum Allahu khairan.