Voice actors are not renowned for being famous. If your goal in life is to be well-known, to be a celebrity, there are a million better ways to accomplish that than by being a voice actor. It truly is a craft and a business where it is wise to do it because you love it.
If you showed 100 people a picture of Homer Simpson and asked them to identify who he is, how many people do you think would correctly identify him? I don't have an answer for this but I think 90 or more people would probably be able to "guess" correctly. That's 9 out of 10 people or greater. I feel this is quite a fair estimate for the main character of one of the most iconic television shows in history. But if you asked 100 people who voices Homer Simpson, how many of them do you think would know this? Well this time, I might have an answer…