I know that German universities are generally free, while, for example, their UK counterparts charge around 10,000 GBP a year.
https://www.moneysavingexpert.com/students/student-loans-tui...
I'm not sure if they account for inflation or have any fixed interest on the loans. 30 years without any would be pretty crazy.
It's basically inflation + 3% if you're earning more than £45k/yr+.
For example, tuition fees at Scottish universities are "free" (i.e. paid for by the Scottish Government) for Scottish residents and people from other EU countries (but not the rest of the UK).