I work for the largest ISP (KPN) and started at €43k for my traineeship about 6 years ago. I'm now at €80k.
€40k is way too low, way way too low. People starting out in regular jobs in healthcare or education without too much education already make €45k.
€45k is 'modaal' in 2024, the modal salary for the entire country.
I think your numbers are about 10 years behind reality.