clogged impeller, if the pump basket has even the slightest crack it will allow debris to pass thru and clog the impeller, baskets can be flimsy on whisper flo pumps, the water movement when looking thru clear pump lid on your pump should be more powerful looking, compared to the weak appearance in video, and the mention of both skimmers also weak when isolated from each other, pretty much rules out skimmer lines being clogged, i have worked on hundreds of pumps over 25 years, (i am a pool repair tech, not a pool cleaner) it doesnt really matter how you clean your leafs from pool for the most part (unless you live in "leaf town") if your pump basket is frequently stuffed full of debris, it will over time split and crack, eventually clogging the impeller because debris passes thru it, so carefully inspect the pump basket, even if you dont see it cracked anywhere, get in the habit of inspecting it, and replacing it for even the smallest cracks, air leaks are most likely not a major problem for you as the pump appeared to be primed in video, when viewed thru pump lid, just had a very weak stagnant appearance regarding water flow/movement in basket area, very common condition with impeller blockage, compared to the normal more forceful water action seen when viewing thru pump lid under optimal conditions 20 psi etc.