That is wrong. The Munich public transport system has been turning a profit for at least 15 years out of the last 17. For the two missing years, I did not find numbers or sources, but it's probably the same.
Pretty sure there are others that run successfully.
BTW only road systems where you pay for every mile you drive (see e.g. motorways in France, Spain, Italy) turn a profit. All others are, basically, just a waste of taxpayers money ;-)
It's usually failed policies and nincompompous administration that make public transport systems fail.
Sources:
>https://translate.google.de/translate?sl=auto&tl=en&js=y&pre...
>https://www.swm.de/dam/swm/dokumente/unternehmen/swm/geschae...