And in that highlighted statement is one of the biggest myths of the war. While construction of large ships, with the exception of Graf Zeppelin, may have stopped in 1942, construction of destroyer sized and smaller continued until almost the end of the war. For example:-Montgomery wrote: ↑01 Aug 2021 11:24May I say the you are simply trying to downsize the effectiveness and importance of U-Boat
By 1942 Germany transferred all service men to U-Boat and directed the industry and shipyards to manufacture U-Boats only!!, because finally Hitler agreed to what Rider and Donitz had been tried hard to convince him in 1939 that U-Boat is more effective to war effort and the war will be decided/Ended faster through U-Boat! this is one of Hitler's/OKW fatal mistake to delay that switch.
Prime Minister Churchill had wrote the UBOAT was his scary nightmares during the first 3 years of the war!! it is simply because of the damage they produced! end of story!
Here the fair closing statement
No body can guarantee - if Donitz had 300 Boats at beginning of 1940 - Britain will be fully blockade ,or forced to armistice !!they will find a way even Air cargo backed up by the US full industry !! - Britain will never surrender !
But there is guarantee that the 300 boats will cause much more damages and more suffering to the British war industry and army.
Graf Zeppelin - work on her continued into 1943.
Destroyers - continued to be laid down until Sept 1943 and Z43, completed in May 1944, was the last completed with others under construction.
Torpedo boats (small destroyers not E-boats) - continued to be laid down into late 1944. The last completion, T36, was in Dec 1944 and work on others continued into 1945.
Minesweepers - the last completion was in April 1945 with many more launched and incomplete or still building on the slips. How else could the Germans hope to keep their waterways open in light of the Allied aerial mining campaign if not by building more minesweepers?
While Raeder resigned in Jan 1943 over Hitler's instruction to mothball the big ships, Donitz reviewed the position immediately upon his appointment and persuaded Hitler to reverse that decision in Feb. So the likes of Tirpitz and Scharnhorst remained in Norway while Admiral Scheer, Lutzow and Hipper became training ships in the Baltic until late 1944 when they were brought forward to support the Army on the Russian Front.
It would probably be better to say that U-boat construction and manning was prioritised in 1942 but not to the exclusion of everything else.