Most of these Avionic systems can be switched back to a basic HSI if you wish so use of these systems is not mandatory and in some cases the full EFIS navigation display can just confuse the situation with too much information, last week I turned off the map and put up the basic HSI to aid clarity during a VOR approach to runway 22R at Nice.
A&C you have a lot of posts and clearly a lot of experience but clearly not much time in a Cirrus as you are not going to be turning off the avionics in a Cirrus and doing an ILS approach anywhere using the basic HSI
