Eurostat average full time salary 2022 for Spain is €31k. 2021 average nurse salary €38k.
While mean is not median the stats seem to show much less of a difference than your figures. For comparison in the US median full time wage is $66k while median nurses wages is $86k.
Nursing is a skilled occupation requiring a bachelors degree. Seems good they get paid around average wages for graduates.
https://ec.europa.eu/eurostat/databrowser/view/nama_10_fte__...
https://www.euronews.com/next/2023/12/14/nurses-salaries-acr...