all credits go to video.
open file browser, and navigate to “system/app/”. root permission required.
rename launcher_*_signed.apk, like launcher_apk.bak. then it will not be installed since next boot.
additionally, you can remove other builtin apps, like facebook lite(com.facebok.lite.apk), ES explorer(EStrongs.apk), etc. by removing these unused apps you can expect shorter boot time, since they will not be deployed any longer.