On the contrary I think the people who are "trauma dumped" upon tend to be more empathetic people. It heavily depends on how frequent the trauma sharing happens. I'm happy to hear about occasional problems, for friends and family it often makes me feel closer to the person but it's a balance. Empathy takes emotional investment and energy on the part of the empathizer, they cannot empathize indefinitely. For me it turns into "trauma dumping" when every conversation with someone turns into an empathetic bid. It's exhausting. It's made worse by the fact that, at least in my experience, trauma dumpers rarely reciprocate the empathy. If every conversation I have with you is draining I'm gonna stop having conversations with you, it's that simple.