Have you used a particle system lib?
The native MacOSX is slow also on AMD GPU, but WebGL works fine on Chrome, also faster (but it not works on Safari)
No, I have developed my personal particle system engine.
Both, as static with only ONE attribute for vertex (4 float: either pos and color), as dynamic with GL TransformFeedback with only TWO attribute for vertex (8 float: pos, color, vel and time)... Yes, Safari have WebGL2 instruction set, but still uses Shading Language Version: ES 1.0, as WebGL 1, and not ES 3.0 as WebGL2 would like...
So Safari is not "full" WebGL2 compliant... And yes, the native code for MacOSX is slower: Apple have deprecated OpenGL, so drivers are not optimized for it, and version is stopped to 4.1