I'm about to start working with a guy who was born in China, whose last name begins with a 't'. I'm looking forward to learning how to pronounce it.
The Pinyin system of Chinese transliteration (adopted around 1979) is probably more consistent and easier to handle than the older Wade-Giles method, but it's really hard to guess whether the name of a person of Chinese descent uses the old system or the new one. You just have to ask and listen carefully.
Once upon a time, I was barely aware of Wade-Giles.
I worked in the late 1960's at a company that employed a good computer programmer named Helen Tu. (We pronounced the 't' as a 't' sound.) I was her manager for a while. After some years, her husband got a job far away and she resigned. She asked a few of us to come to her home to help with a little packing, and we happily agreed.
She was proud of her five year old son Eugene. She had pictures of him in her office, but we had never met him. When we got to her home, he came barreling out with his mother to meet us.
"So this is the marvelous Eugene Tu, that I've heard so much about," I said.
"Eugene Du," she replied, and I had an "Oh, my God" moment. I realized that for years, everyone at work had mis-pronounced her last name. She must have felt that it would be impolite to correct us, but she had every right to make sure we pronounced her son's name correctly. And she did.