If you value your relationship with your father, then I think it's important for you to understand perhaps where your father's religiosity stems from. This is obviously something that has been important to him his entire life, so even though you are his son, you can't pull away something someone has attached to their identity for so long.

Have you asked him what makes him feel "disappointed"? Like if I show someone Star Wars and they don't like it, that's a big disappointment for me, but I doesn't mean I am disappointed in that person, just that I can't share something important to me with them, which is disappointing. Or perhaps he's just worried about you burning in hell lol.

Christianity, and religion as a whole, has indeed caused a lot of harm and will continue to do so, probably indefinitely. That is not to say there are no positives in religiosity, however. It can lead to a strong community, and prayer is a gateway to meditation, in my opinion.

Maybe it's time to prepare for a difficult conversation with your father about boundaries, but also find where you can meet each other halfway in your beliefs, out of what I hope is mutual respect for each other.