@saki2006 Dyntopo has definitely changed a key thing since this video was recorded: The detail size values. When this was recorded I typically started at 30 px for basic shape sculpting, then 20 px for mid-level sculpting, then 10 px for details.
With current Blender I generally use 10 px, 7 px, and 5 px respectively. Try that and the experience should be much more similar.