The former Lionhead boss told Edge he's certain Microsoft will eventually release an Xbox One console without the motion sensing device.
The British game designer, who left his role as creative director of European studios for Microsoft Games Studios in early 2012 to form Godus maker 22 Cans, said Kinect "feels like an unnecessary add-on to me".
He explained: "Maybe it's because we're in England, and it doesn't really use the TV stuff, but it feels more and more like a joke. My son and I sit there saying random things at it, and it doesn't work.
"They could cost-reduce it [by removing Kinect]," Molyneux added. "I'm sure they're going to release an Xbox One without Kinect. It would be unthinkable that they wouldn't."
Microsoft has consistently denied suggestions that it may one day release a Kinect-free Xbox One console by labelling the motion sensing device "an absolutely integral part of the experience". And Phil Spencer, who was promoted to head of Xbox in March, told Edge dropping Kinect isn't top of consumers' Xbox One wishlist.
"We're always trying to match what consumers are asking for," he said. "I always want to make sure that we're in tune with what current or potential customers are asking for from us. Right now, [dropping Kinect is] not the number one request from people. Usually it's, 'Where are the great games?' There are a number of games on the ID@Xbox programme that use Kinect, and you'll see more games in the fall."
Flagship Xbox One Kinect game Kinect Sports Rivals was originally scheduled to be a console launch title in November 2013, but Microsoft delayed it to give Rare extra time to polish the game. The Kinect Sports Rivals release date is today, April 8 in North America and Australia, and April 11 in Europe.
In our Kinect Sports Rivals review we praised the Xbox One title for delivering "motion gaming for everyone - core gamers included". See what other critics thought of the game in our Kinect Sports Rivals round review-up, which features scores alongside short excerpts from a number of verdicts.