@FrostedFoxes it's regional. In Japan, you won't find much names that start and contain the letter L because of it (names that start and contain with R are quite common though)
In China, the situation is reserved. Lots of L names, but not much R.
Since we're at a global age, this issue is slowly being addressed by the newer generation and sooner or later, this little quirk will probably disappear.
EDIT: Chinese friend tells me they DO have an 'r' sound, but it's more guttural and unlike the english version.