While no one can say with 110%+ accuracy whether or not the outcome of Churchill's decision to destroy what remained of the French Navy in the early 1940's changed the course of WW2 prior to (or even after) the US's' entry into this conflict in late 1941, his decision turned out to be very crucial in developing the Western Allies' (basically the US, Britain, and the USSR) strategy for conducting the war after the D-Day invasion of Nazi-occupied Normandy in June, 1944.
Churchill knew that, had the Nazis captured the French fleet (which was Hitler's plan to do), this would have resulted in almost completely isolating the British Isles from receiving much-needed supplies from both the US and Canada.
Anyone who is familiar with how dangerous it was for our cargo ships to arrive unscathed at British ports due to Hitler's incessant and very deadly U-Boat [submarine] attacks on Allied shipping in the Atlantic Ocean can only imagine how much more impossible it would have been had these cargo ships also had to deal with bombardments and/or raids by Nazi-operated battleships and cruisers!
Some WW2 military historical analysts contend that Hitler never really considered an Allied invasion of northwestern Europe as being very feasible. According to some of these analysts, this is why Hitler never allotted that many resources in developing a very strong system of coastal defensive fortifications--a mistake that proved to be very costly for him on D-Day.
While it is true that the US and British military allies did expend a large degree of their resources in fighting Rommel's "Afrika Korps" in northern Africa, when the Allied military strategists came to the conclusion that Hitler was more concerned with protecting his "southern" and "eastern" flanks (i.e., respectively the Mediterranean and Balkan [SE Europe] regions), that was most likely the Allies' principal impetus in proceeding with "Operation Overlord"--the official designation of the initial 1944 military invasion of northern France. ("D-Day" was only the initial coastal invasion phase of "Overlord.")
For those who may be interested in studying this interesting and (as was pointed out in the OP) relatively "forgotten" aspect of WW2, in addition to the sources referenced in the OP's on-line link, I can also recommend a complete biographical narrative on Churchill's life written by Sir Martin Gilbert entitled
Churchill: The Power of Words published in 2012 by DaCapo Press (ISBN 978-0-306-82155-4) [
www.dacapopress.com ].