That is certainly one way of interpreting the guidelines.
The other way is that the funding is very limited and those who are able to get most benefit from the extra expense are prioritised.
I would definitely not interpret a challenge managing our diabetes with MDI as "sizeable mismanagement". There are many reasons why some find MDI difficult both physical and mental. For example, I was eligible for a pump due to frequent hypos when exercising. I exercise more than most but over many years trying many different techniques, I was not able to find a method that allowed me to exercise at my peak whist avoiding hypos with a long term basal insulin. Others need the smaller bolus dose to avoid hypos.
And, in my experience, a pump is not an easy option.
I consider a funded pump a huge privilege not something I expect.
Maybe I would say that because I am one of the "lucky" ones who have a pump ... although I did not consider myself lucky when I was expeciencing all those hypos when trying to keep myself fit.