If by 'that feature' you mean the sort by perceived importance vs. time, I hope they make that possible to configure.
If you instead mean the suggestion of additional content into your feed - that's really the core point of Prismatic. I wouldn't expect to see that configurable / given an "off" switch ever. In fact, I'm pretty sure that's how they'll monetize the product - slipping in pay-for-placement content that's relevant to what you're reading.
If it can I could never find it. I tried the service out twice and both times found it to try and show me a lot of stuff I didn't want to see and never improved on that front.
If you instead mean the suggestion of additional content into your feed - that's really the core point of Prismatic. I wouldn't expect to see that configurable / given an "off" switch ever. In fact, I'm pretty sure that's how they'll monetize the product - slipping in pay-for-placement content that's relevant to what you're reading.