Well I am also a new player and there is something I wanted to post and it is because when you are in a settlement and you have not collected anything yet I simply load the game from online mode to solo mode (avoid meeting other players) and when loading the game Magically all the materials to collect that I haven't collected yet disappear as if I were cheating (in my case I go from planet to planet to collect, I don't reload the game) and why don't they do that in places like DAV'S HOPE?
Its an intended mechanic to keep cmdrs from relogin in order to farming on-foot materials.... Only apply to on-foot. All due relogin was made too popular among cmdrs due of davs hope and such, while Fdevs admited that a while ago, that they dont wanna see happen that again with their latest gameplay loop, and they could not done better than this.
Exiting game while being already in settlement, at load will not spawn anything to pick up, but there is way to work around it, to reset any instance, a classic instance reset that always will work since its how game engine works: Its quite simple.
But if you go back to ya ship, fly up, enter supercruz and go back to same settlement right away, materials, data panels, anything will respawn.
Not as fast as relogin, but not somewhat long either, it takes what, about 2 mins to do it if done right. It means you can kill entire settlement, grab all items it had, take power regulator out, but once instance is reset, all dead npcs are replaced with other npcs, new materials will spawn (its random each time), in places where these should be, power will be on, with its regulator as if never happend. Not very realistic, but thats how this game works. Persistency only is happen when multiple cmdrs are in same instance, and when there is someone to keep current "state" of instance, when someone else log out and in.
Of course, doing that repeateadly against non-anarchy fractions will make them hostile in no time, well as notoriety at 10, but with anarchy fractions, it can be done infinitely without any rep loss, because at anarchies you dont gain fines/bounties in normal way.