Bug or Limit of ArcgisPro?

Video created by Rosario85 on Jan 29, 2020

    Hi, I have a workstation with 32 GB RAM , GPU NVIDIA TITAN 1000 8GB RAM, SSD, I7 9750H 2,6Ghz,

     

    When i open a layer with (6205750 points) is faster but when i apply standard symbology become very slow (i've attached a new video).

     

    I don't understand why...

    Is It a bug of Arcgis Pro?