from wiki:
“Before D-Day, to disrupt German logistics efforts, the Allies spent considerable effort in bombing the French rail network, although aware this would also affect their own operations in the event of a breakout. The plan of Overlord had foreseen this, and it called for the exploitation of the ports in Brittany to move the supply points forward as the armies moved.
By August, supply sources for the armies were still limited to the original invasion beaches, the nearby deep water port of Cherbourg at the tip of the Cotentin peninsula, and some minor ports in Normandy. Although over-the-beach supply operations outperformed expectations, September saw deteriorating weather and rising seas, and the end of their usefulness was clearly in sight. Additional deepwater ports were therefore required; Cherbourg was useful, but it was far from the front. The Brittany ports, still occupied by stiff German resistance, were equally unsuitable as they were situated along the western coast of France and were overcome by the rapid Allied advance toward the east.
On 4 September, Montgomery’s troops captured the massive port of Antwerp virtually intact, but the Scheldt Estuary leading to it was still under German control. Some argued that the capture of Le Havre and Antwerp made the original plan of clearing French ports further south unnecessary. Antwerp could have been opened sooner by the Canadian Army if Montgomery had given priority to clearing the approaches, but Eisenhower and Montgomery persisted with the original plans to capture many of the French ports.
The failure to open the harbours in Antwerp has been called “one of the greatest tactical mistakes of the war”.
https://en.wikipedia.org/wiki/Operation_Market_Garden
I still find it amazing that the bulk of The Netherlands was still in German hands at the end of the war.
Yes, Monty’s failure to clear the Scheldt had long term complications for the push east. Even Churchill privately castigated Montgomery for that failure.
The French rail system had to be bombed to deny it’s use to the Germans, leaving the ports more important than ever.
For whatever reason Monty seemed to be able to talk Ike into whatever Monty wanted.
On hearing that a captured German General was “invited” to dinner by Montgomery Churchill was noted as saying he felt bad for the German “as I have also suffered a dinner with Montgomery where the sole focus of conversation was...Montgomery!”
One observer stated that Montgomery had the snootiness of the worst European aristocrat, an ego larger than Pattons, the prickly personality of de Gaulle and the inability to understand why no one liked him.