I think is both harm because some parts of a culture are gonna be lost and benefit it’s gonna have a larger variety of traditions On culture is always gonna overshadow the other
This question is personal opinion but I would say that it is good as it brings different people together. It introduces new foods, ideas, and livelihoods that wouldn't have been present without the clashing of cultures.
I believe it is existentialism but I'm not sure. It could also be nihilism or objectivism depending on which philosopher, time period and context of your question. But I'm like 98% sure it's existentialism.
