Here it likely was the exact opposite: the long tail of low-paying clients is annoying to manage compared to how much they bring cumulatively. So the client had been given a choice of either becoming a high-paying client or stop being a client altogether.
The shadow IT model isn't the dominant one in the space where Salesforce play. They used that to a degree too when they were small, but they now lean towards enterprise sales. Shadow IT is sold as a risk by them. Want something secure, safe, and compliant? Work with us because we'll sign up to these things contractually (even if delivery is questionable.)
This means that a slack salesperson has to choose between targeting a department and pissing off IT versus working on a company-level deal. This changes behavior significantly. It also changes lots of the economic expectations. Previously, these little deals here and there could add up. On top, you might get credit from driving engagement. Now you carry a much larger quota where engagement is important in practice, but not in how sales is executed.
This drives the behavior you see here. Someone is reevaluating each of the current deals with this new lens. In practice, they can maximize revenue with these bullying tactics. Many times, in the enterprise space, it's better for a customer to be cut off, or give up, even if this is temporary. The intention is for the customer to return and agree to different terms even if the financials are adjusted to something more favorable.