Sure, but I don't think Collins is Nationals only problem.
As long as they allow Peter Goodfellow to hold his iron grip on the party and allow him to appoint his and his friends buddies to MP's without proper character check and without requiring leadership qualities National will stay screwed.
As long as they pussy-foot with (more or less concealed) antivaxxers, conspiracy theory spreaders, gun lovers and activist farmers who fight for the right of town folks to cheaply drive big and for them absolutely useless SUV's they will stay for many unelectable. Certainly for me.
Lots to tidy up ... and not sure whether any substance will be left when they remove all the scum in their party.