I never knew this. Ill have to find more detailed instructions to put it to the test xD.
It used to allow 2 people on pc to play games at the same time with one subscription. But recently I've found it no longer works. FH3 and FH4 I had one sub and we both played on pc together with it fine. But AOE4 kept booting us to desktop. Different pc though so maybe I just set it up wrong this time.
Yeah beware. I was playing FS2020 (Steam version) and my kid wanted to play learn 2 fly on his laptop (free game on Steam). I let him log in on my account instead of making a new account. A free 2 play game, should work fine, I can play 2 different steam games on my laptop at the same time after all. FS2020 + Road 96 had no issues. It worked for a while then I suddenly got signed out of XBox Live, FS2020 closed, Steam started asking for credentials. Plane and all passengers lost over Northern Canada.
The disadvantages from digital, although GT Sport doesn't mind my one copy being used by my other kid while I race on my account. But I guess that's 2 different accounts, he's just using my primary ps4 to play on a different account. (I do get signed out immediately without warning if he boots up his ps4 with my account)
How did it work in the old days, I simply started IL-2 Sturmovik on one PC first, then put the disc into another PC, started the game there, then we were playing in LAN together with one copy. No accounts, no problems :)