Government hasn’t made it worse by itself, a combination of Network Rail and northern mismanagement alongside a long term strategic campaign of industrial action by the RMT have done so
The DfT's tender and Network Rail's failings are the main causes of the problems with performance, reliability and delivery. These are ultimately the responsibility of the government. I certainly don't absolve the company of their responsibility, they seem to be doing flat out nothing to make rail travel more attractive. Doubtless there have been some policy choices in their direct control that have made the problems worse, not least with regards to the speed of price rises, which should have been slower, ans a totally botched introduction of Penalty Fares, that ignores their own rules. However, it is less clear exactly what they've done to contribute towards the mess.
Regardless, on the whole, I would say that by most measures (targets and performance, reputation and growth trajectory and financial and commercial), the franchise is in a worse position now than it was on the first day of the Arriva Rail North tenure. This is a shared failure for everyone.