Well, if it was a simple question I would've likely known the answer already, right? An increase of 20% from low to high is definitely notable, but hard to see why one would need to be desperately worried. As you said, GINI is fairly abstract and there's no 1-to-1 link between somewhat higher GINI and starkly increased human suffering. The average person is way more rich now than in 1980, and human suffering has globally gone down.
With that said, there's also no reason I can see to try and intentionally get GINI higher. The fact that it's been at a lower number also proves that reducing it is entirely possible, which is what I expect would happen if relatively high GINI proves to be a problem. I wonder if the information age has mechanisms that causes GINI to trend upwards, or if it is strictly based on policy.