It's true, and it is not just a Dutch problem. Basically all major river systems change throughout the centuries: meandering arms evolve and others get cut off;

It's true, and it is not just a Dutch problem. Basically all major river systems change throughout the centuries: meandering arms evolve and others get cut off; river deltas grow and change shape and of course human activity shapes the landscape (canals, irrigation, drainage of swamps and floodplains etc.). The ancient city of Eridu for example was a coastal city around 5000BC and today lies hundreds of km inland.