If you read Scripture, you will find the command to raise our hands.
1 Timothy 2:8, in fact.
It doesn’t mean that this is the only POSSIBLE way to worship. I’d find it rather hard to do that while being a pianist in a church ensemble, for instance. (OK, I lift them to the keyboard.) But as the Lord prompts it is right for people to obey.
Funny, never saw that in a Catholic Church or any services from the Vatican, etc. Perhaps you should send them a note to read scripture? They’re obviously not in the know.