There's plenty of reasons to regret signing him.
a) He's being paid like a top 10 goalie, and his play hasn't been close to that level
b) He hasn't been in the lineup consistently
c) It's become clear that his contract and tenure won't line up with our competitive window
We're not competing this year. Chances are, we won't be competing next year (being a bubble team would be great). Realistically, we won't be a playoff team until 2023-24 - the last year of Murray's deal. After that, he probably won't be back.
Hindsight is 20/20, but in hindsight, we would have been better off signing an older, cheaper, more dependable veteran goalie who could play 30-50 games, mentor Gustavsson, and free up payroll for some of the other glaring holes on this roster.
James Reimer. Petr Mrazek. Jonathan Bernier. Anti Raanta. All would have been better options.
Murray was a mistake. Let's call a spade a spade. We'll pay him ~$20M and he'll, if we're lucky, play in one playoff run for us. Although the way it's going, it's more likely that he's the back-up when we make it.