For the first 6-7000 rounds all I ever did was oil mine.
Except when it started to malfunction, Then it got hosed down with brake cleaner and re oiled.
My gas piston has suffered after around 10000 rounds to the point that I just got a nice new one to replace it with.
I am sure I have not done the bore any good but it is fairly dry where I live so the rusting was very minimal
When It went camping in a tent I noticed a lot of rust very quickly and oiled it real well.
I have never taken the firing pin out of my SKS. Period
Recently I did however start with the hot water treatments then oiling.
I guess what I'm saying is that:
1 It is a cheep rifle that I shoot a lot
2 It will never be a collector rifle (It will wear out first lol)
3 It depends how much you like cleaning them...(I hate it lol)
If water is put on it you better dry it soon after and re oil it.
Or just oil it real well (if you wear glasses the next time you shoot it you better have tissues with you)
My boy rocking it this spring at a 75 or so foot high sand hill

It has easily had 8500 rounds thru it at this point in time...
https://youtu.be/gGkcbf9c2sM