Well yes, the idea is to have more people use the trains, so yes also more trains are needed(and more investment and replacement of the Bahn management) in general, but as far as I know there is no income taken away, as it is subsidized and compensated on the federal level.
Problem with this approach though is it makes the system very vulnerable to political changes. How much of a problem this is in Germany I'm not sure.
> no income taken away, as it is subsidized and compensated on the federal level
Only 50% of the relative loss of transit agencies is subsidised by the federal government, the other 50% gets subsidised by the respective state. And since the compensation is calculated in relation to the prices of monthly subscription tickets on routes in the respective transit area, transit agencies are left with even less.
Additionally, a lawsuit determined that the train network price cap for public transport is illegal, further increasing costs for the states.
This already has caused service reductions in multiple states, e.g. just now in Berlin additional overground Metro services during commuter peaks got halfed. With the results of the lawsuit and now interest from the federal goverment to put more funding into public transport, a lot more services will get axed in the next 3 years.