First off, I'm a firm believer in the ore restrictions for portals. At first glance, it seems like an unnecessary grind element. But it's not, at least not while you're still "beating the game." It forces exploration, outpost building, which in turn forces players into those crazy, interesting, random encounters that make Valheim come alive.
With that said, once you reach the end game, it becomes a pain. Especially, if you just want to build. And no, I don't want to play in creative. I prefer the diversity of the game loops in survival, even when I'm wholly focused on building. Yes, I know there's a mod for it, but this would only apply to PC players who want/know how to mod.
Iron Gate should just make no portal restrictions an end-game boss power. Having a countdown timer on it makes sense too, so there's still an element of planning and thought that must go into transferring ore. What would be the downsides to this?
Sorry if this has been suggested before.
Source: https://www.reddit.com/r/valheim/comments/12me4oq/a_portal_ore_idea_probably_been_suggested_before/