Hello!
Thank you for your feedback.
For the context, in this topic we're discussing the PvP resource domination mechanic and in particular oil and Li deposits that PvP players can capture. It doesn't apply to PvE servers (there is no such mechanic).
1. The oil and Li resource deposits are not infinite. When you hover your mouse cursor over them you will see how much time they will remain in the current location (even if they're not actively mined). Once that time has passed, the resource deposit is destroyed and respawns within 30-60 minutes. The online players receive a notification about the deposit spawn and can go to attempt capturing the resource deposit (the event lasts around 30 minutes, the notification requires learning Xenogeology tech from Tier 3).
2. You can build extractors without capturing a deposit—the output will be 4 times lower but it's reasonable considering that it's practically risk-free. Though it will not provide your faction with the faction points for controlling resource deposits.
3. Besides, you can gather oilpods in the temperate and boreal forests, and mine lithium salts in the desert. So there are alternative sources of oil/Li as well!
4. Regarding the idea that you've proposed that the shield should drop on all the bases simultaneously. Imagine some players that are playing in a group. They will be extremely unhappy if every time anyone of them joins the game all their bases are losing the shield (and so could be raided very easily). It will make the game just unplayable for the majority of players that have groups, and it will also discourage players from playing outside their group's prime time (resulting in a lower online number overall) as nobody wants to risk their primary base by simply going online.
The current approach allows players to have several independent bases (often managed by different members inside the faction). Many player factions on the servers such as Global PvP have an almost 24/7 presence due to some faction members playing in different time zones.
Regards!