Possessing carriers and knowing how to use them are two different things.
The major naval air powers had been involved in developing carrier operations for many years. It could hardly be expected that the Germans could field a competent naval air component, developed from scratch, even if by some miracle that the carriers of the Royal Navy were to fall into their laps. I am sure that some of our UK friends could provide numbers on how many Royal Navy ships were in US harbors on any given day.

Germany would still have faced the oil shortages that plagued them throughout the war, impeding pilot training much as it did in the real thing. Looking at the years 1942, 43 and 44, German crude oil production, added to British production would still have been only 1/8th of the US output (70million metric tons verses 830). And that is assuming that Germany would have access to British overseas oil fields, which I doubt strongly that they would.

Where would these German carriers come from? German (actually European) steel production stayed constant throughout the war as did the other combatants on both sides. This is despite Bomber Command and the Eighth bombing German cities and the countryside. Iron and steel production was barely enough to supply the army needs in the real war and I see no reason that Hitler would have delayed Barbarossa, thus sticking his hand in the tar baby just like what actually transpired. Adding full British production to Germany's for the same years, it is still less than half of the US production, 1498.3 million metric tons to 3095. In 1945 alone, the US was on pace to nearly equal German production for the referenced years combined, producing 86.6 million metic tons, Jan to Aug 1945.

Aluminum is critical to airframe construction. Carriers without aircraft are useless, just ask Adm Jisaburo Ozawa of the IJN. In the real world Germany was greatly crimped by aluminum shortages. Even adding in full British production for the years mentioned above, German production was still less than half of the US. I doubt once again that all British bauxite would accessible to the Nazis, probably being added to the US side of the ledger. US aircraft production, with somehow adding British production to the Germans, would still be 3 times both of those countries combined. And this is a generic number, including large numbers of 4 engines bombers, which Germany produced in miniscule numbers. Yes, I know that Britain produce bombers too, but not in numbers like the US. You can build a lot of carrier aircraft out of a B-17, if they so needed.

The US built 90 divisions and probably had enough non-divisional resources to build at least 8 or 10 or more, plus 6 Marine divisions. Better than a third of the army divisions were in the Pacific. After the Japanese capitulation, these divisions and their landing craft, plus the Marines would be available for combat in the Atlantic. Up until June 6, 1944, 70% of German ground forces were facing the Soviets, in Dec 1943 the number was was 93%. I see no reason that this number would be any different, except that maybe Norway could have been garrisoned with a few less than the 12 that were there. Bear in mind that a German division in 1944 was about half the size of a US division and see no reason that the numbers would be substantially different from the real war.

For such an incompetent bunch, the US Navy sure sank a lot of U-boats, not to mention Japanese boats. Give me a few days and I can give you numbers if you want them. The only successful submarine anti-shipping campaign ever in history was conducted by the US Navy against the IJN. I would highly suspect that the DKM would be even less able to protect its ships from sub attack than were the Japanese.

If you want sources for my numbers, I can give them to you.

Can you make your argument in the same manner?

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Best Regards,
JW