https://zachholman.com/posts/streaks/
Personally, I find the contribution chart both motivating and frustrating. The contribution chart is enough of a signal that I try to make sure it looks healthy each week. But, at the same time, it's far from a perfect tool for assessing how productive I am, because commits come in all shapes and sizes. And like any gamified metric, it can lead to unhealthy obsessions.
Arguably anyone who falls for gamification has "a problem," to one degree or another. But if we know that certain personalities are more likely to have unhealthy obsessions with something, that's maybe a good reason to take it down, or at least lessen the focus on the "streak" and represent activity more positively without highlighting the gaps.