The post asks: "When does it end?"
It ends when DXC collapses completely. Mr Shouty will continue to cut until there's nothing left. He doesn't understand the basic concept that customer service requires the right number of good, motivated, people if you're to keep a customer happy.
The more he cuts, the more customers leave. The more customers leave, the more he cuts. He's shown that he either can't, or won't, end the cycle. So it continues until DXC quietly breathes its last, and its competitors take over the customer accounts.
Of course, you can make it end faster by going elsewhere and working for a better employer yourself. I did, and I can assure you I don't regret it!