Seems that playcanvas convert fbx animation to frame data evaluated in every 0.1 seconds.
This will produce a very large animation json file for a long animation stack, even though the stack contains only two key frames.
@anon49240888 if you have a fbx animation of 10 key frames that lasts for 5 seconds, playcanvas will convert it to 50 frames, each frame for 0.1 second .