The Wayne version was cooked up between he & legendary stuntman Yakima Canutt specifically for the original Stagecoach movie.
It's purpose was to enable Wayne's character to carry a very different & showy gun, and to allow him to spincock it.
The Rifleman's version was created largely for the same reason, with the added attraction of the rapid-firing capability using a set-screw on the lever and a further modification on the receiver itself to keep blanks from falling out while the 20-inch carbine was spun.
Today, there are various makers such as Wild West Guns, DRC, and Brockman who produce different versions & configurations of enlarged levers, and those are for more finger room with or without gloves. They are not configured for spincocking, and do offer some practicality.
The more exaggerated & larger loops offered by Winchester/USRAC from the late 1980s till the New Haven plant closed in 2006 were intended more for show and nostalgia. Same with the one listed on the current Winchester site made in Japan by Miroku.
Ditto with Rossi 92 versions sold by Legacy Sports in the past, and current Italian-made Puma-branded 92s sold by Legacy.
The large loop is somewhat slower, as the Cowboy Action Shooters found, since there's more room to bounce your hand around inside the lever loop while cycling the gun.
I've found on my .30-30 Win Model 94 Trapper the large loop gives me better leverage (it's longer) in working the heavily sprung rebounding hammer action.
I tried that gun with & without, and kept the big loop on it.
Coincidentally & parenthetically, while I do not advise such things at your place, I did find the .30-30 can be spincocked IF ABSOLUTELY NECESSARY and run one-handed in an injured-off-hand scenario.
Not always the case in pistol-calibered 94 or 92s. May or may not feed or chamber.
I have a Miroku 92 here at the moment, with rebounding hammer. It's the 20-inch standard carbine, not the 16-incher with the big loop.
I have no doubt the bigger loop would give me the same leverage advantage on it as it does in the .30-30 94, with the current actions on these Winchesters. A shade slower, yes, but with some practice & muscle memory the big loop can be run decently by using the right technique, and for most occasional users, hunters, or plinkers, the difference in speed is no issue at all.
Denis