Some things respawn. Enemies (meat, neck tail, leather, bone, entrails, resin, wood, etc.) respawn and that means whatever they drop is in infinite supply. You can grow more trees. Berry bushes regrow the berries after a while. Fish are abundant. Flint respawns. Single rocks and single pieces of wood respawn. Surtling cores become far easier to obtain.

Right now copper, tin, iron, and silver don't seem to respawn, although I've read some forum posts from players who will tell you they've seen some ores respawn but I have never noticed it. You can find ore in other places as well, I've had some drop from a variety of sources but it's usually super rare.

Sounds a bit like your group had no idea how to share and cooperate. Also sounds like you didn't send smaller teams in different directions and instead used the lemming method. The game world is big enough that you can find all the resources you'll ever need if you explore.
If that's too tough, unappealing, or annoying just jump on a new map for a little while to gather what you need, then go back with your loot and re-join the rest of the group.

The game should be easier with a group, not harder, so I'd say talk to the group and explain the issue. If your team can't come to an agreement on how to play then may be you need to split into two groups of four, or split the duo that rushes and make a group of the 6 who don't rush ahead. The group that tends to lag behind could just start a new map and play there, and join the others for boss fights. Loads of options.