The safety pilot issue is not well understood as people don’t understand that you can be complying with IFR but be VMC, so you can fly an ILS in visual conditions while complying with IFR and under radar control and not need a safety pilot.
If you are flying VFR under VMC to practice an ILS then you are respondable for your own separation from another aircraft so you need a competent observer ( NOTE NOT a pilot ) to ensure you can maintain seperation from other aircraft.
Ther key to understanding this is knowing the difference between RULES and CONDITIONS.