Not saying maintenance isn't a problem, it probably is. It's a problem everywhere in Europe. Have you seen train service in England, Germany or Sweden? Absolutely terrible, compared to just two decades ago.

But under-maintenance causes trains to stand still and be late. It does not cause them to crash.

Crashes are caused by running at speeds higher than the (under-maintained) rail can support, or (against all rules and every regulation) no cap on speed when the signalling system is down.

The latter can not be solved with more money and resources. It is a culture problem. Rules can not routinely be disregarded for arbitrary reasons, especially not when they are completely in line with common sense.