A substantial number of people commit suicide following loss of one's job. Would you feel it's fair to say that their bosses drove them to suicide?

I'd say no. Most of such cases, like Swartz, had existing mental conditions that are primarily responsible for their decision to commit suicide. Loss of a job may have been the event that ultimately prompted the act, but the driving factors were mental conditions. Saying that these people were driven to suicide conflates these cases with like this where someone is actively driving someone else to suicide: https://en.wikipedia.org/wiki/Death_of_Conrad_Roy