The were making 8.5 per hour which above the 2026 youth wage.
They also are relating a story from their past and since they have had an account since 2015, I am assuming their youthful past was at least 1 decade ago if not nearly 20 years ago.
No, the 340 were per month, the 40 hours are per week. I usually do back-of-the-envelope calculations with 4.3 weeks per month, which would leave them below 2 EUR/h.
Edit: But you are of course right about inflation! According to this website[1] it would bump them to 3.2 EUR/h.
Minimum jeugdloon exists since 1974. Of course the numbers change but the ratio doesn't.
Look at it like this: if 18y minimum wage was €3 back then and would double to €6 at 21y, and you're a construction worker working for €8.50 at 18y, you're sure as shit going to demand a raise at 19, 20 and 21 because all the people making minimum wage are getting those raises too. Maybe not a doubling, but you wouldn't (shouldn't) gnash your teeth and still make €8.50 three years later.
They also are relating a story from their past and since they have had an account since 2015, I am assuming their youthful past was at least 1 decade ago if not nearly 20 years ago.