Still looking for the research article in which I read that statistic, or another article with a link that doesn't require you to buy the article to read it, and it is admittedly based on the assumption of a certain skill level. Also, if I recall, it is also non-right lateral handedness rather than pure left handedness, which means ambidextrous and cross-dominant violinists might also be included. If violinists are everyone from virtuoso to just bought an instrument yesterday, then you are talking much closer to the ten percent we see in the general population. I did find the statistic for musicians in general in a credible source, which is 4% higher than the general population and therefore still an overrepresentation if not quite as large.
But you know, you can't use personal experience as a judgement for whether a statistic is accurate because you don't know if your "sample" is representative or if your observations yield accurate data. There are left-hand dominant people who are not so obviously left-hand dominant, either because you don't interact with them in a capacity in which you see them write or because handedness is more of a spectrum than an either/or absolute.