If Technicians want to hide Asset field during template loading, then the same can be achieved using Execute Script option in Field and Form Rules.

Edit the incident/service template from which the asset needs to be hidden, choose Field & Form Rule tab. Create a rule "On Load" with the below script.

jQuery('[name=selectedCIs]').parents('div.mb0').hide(); 
//Hiding the asset in details page (In-line Edit) 
try{
  jQuery('#multiasset').parents().eq(0).hide();
}catch(e){}

and save.

This will hide the asset when the template is selected.