It's funny, in BC when I was there, everyone used Craiglist. Was a real shock coming to Ontario to find everyone on Kijiji. I personally much preferred the minimalist and clean interface of Craigslist, but considering both are being killed by FB Marketplace, it's clear that interface isn't what drives people to a site.
I personally hate Marketplace for having a terrible search function, forcing the use of Messenger, and making it needlessly difficult/near impossible to search listings provincially and nationally. It's also Bookface, the worst of the internet distilled.
But having sold off a bunch of unused bits and pieces through the fall, (as well as selling an Aprilia and buying a Guzzi) at least 90% of sales came via Marketplace. I posted everything on both, but Kijiji just had a lot less action. I have a few search alerts active there as well, and the hits coming back are fewer and fewer, so it's clear the site use is dying off fast...