It isn't going to be difficult to implement what they've implemented? Not shit? Your opening statement is confusing.
Harvesting and crafting is already deeply tied to every part of the game, so much so that sieging/defending requires an entire guild's engagement (read: grinding mats) to participate in the end game in any meaningful way.
Investing for the sake of investing isn't intrisically fun for the same reason making commitments in life doesn't have immediate gratification. We typically honor our commitments because we have an understanding that the long term payoff is worth it, which again, isn't inherently "fun". The devs are asking people to invest a lot of time and log in again in the hopes that some day down the road it will pay off with little to no immediate gratification. There's no inherent fun there.
The devs need to do a better job of showing players how their actions today add real value to the progression of the game. I mean that currently it's difficult to see how a player harvesting wood or cooking has immediate pay off other than already being committed to a bigger cause. Which, creates a big challenge. The devs are requiring players to come in already being committed, instead of leading players to make that decision within the game because "worth it".
Currently, it would seem, the entire premise of the end game is that those who grind more win. That's how heavily resources are already tied to the end game. The inherent problem in this is that other than getting a small bump in XP, the individual player receives no incentive or reward in the short-term. The reward is that a player's commitment will eventually pay off in the end game...maybe...if everyone around them is equally committed.
Compare this to games like WoW/EQ, where there were obvious rewards in the short term. Obvious skill and talent paths, different color loots, dungeons, and zones as an incentive to progress. Then, periodically, entire guilds could come together to pursue even better loots, dungeons, and zones. There was both a short term reward and an obvious reason to commit to something larger. "Hey I've been getting 1x, but if I show up to raid every night, I'll get 10x." New World is way more sandboxy with way less value placed on things like skills, talents, and loot because the game is mostly player-skill based. I don't think they've been able to overcome the challenge of tieing the individual and group incentives together. But, I hope they do.