She didn't call Nurse Jenny, she sent her a facebook message, and it would have been political point scoring if Jacinda brought it up but the question was asked of her.
Lets hope she do's the same for NZ ICU nurses at the next pay round.
There is a bit of a difference between Jacinda's social message (responding to a globalised praise of Nurse Jenny by Boris Johnson) vs her institutional responsibility (of sorts, as a head of government) towards all our nurses. She has to do both. One does not exclude the other. But the first one costs her nothing, the other one is a team effort and it costs money.
You might have also heard her publicly telling off DHBs on the news this morning for DHBs not paying wage suport to nurses on casual contracts: https://www.rnz.co.nz/news/national/414164/covid-19-publicly-funded-workers-ineligible-for-subsidy-should-continue-to-be-paid-pm