T is often a difficult sound to grasp for non-native speakers of English, and it isn’t because the sound is hard to pronounce. Instead, it is because what we think of as the “T sound” is actually composed of several different sounds, and pronouncing the T correctly requires an understanding of the rules surrounding which version to use in a given word.
There are many sounds in English, but people often have trouble with R. What makes this sound harder for some people to pronounce, even into adulthood?
Toronto - Is it actually pronounced T'ron-ah? Here is the truth: we don't pronounce Toronto as T-ron-ah. As a native Torontonian (or Mississaugian - I can't find any reference to what you call a person from Mississauga), I can assure you that most people from the GTA pronounce Toronto, "Tron-TOE" or "Tron-OH" because we are collectively to rushed to pronounce the first "oh."