Based on the post I’m linking below, 1% is about right. The top graph showed 28,000 users apparently, and an eye-estimate shows around 200-300 people at level 60. Assuming 280, that would be 1%
The difference is pretty great, considering 0.01% would be 2.8 people (meaning completely false based on Leebo, Syphus, and TameneginoKame alone, listing level 60s off the top of my head), while 5% would be over 1000 users, which seems unlikely.