the way i see it all stereotypes which are imposed on a people are negative, the only potentially good stereotypes are ones the a people themselves chose to identify with.
Even then, "positive stereotypes" embraced by a community still cause a lot of harm, especially when those stereotypes originate outside the community. Like Asians being "model minorities" or Black men having "BBCs"
I've often had a similar thought, for me the quintessential example is the spiritual indigenous person who is naive to the modern world, when in fact the group contains individuals of varying levels of spirituality and naivety, just like every group. While it is often well meaning trying to promote a 'positive' stereotype in response to racism is not especially helpful.
That is my white, cis, male take. I'd be interested in any minority opinions.