I couldn't find Justin Boone's specific "fade" take on Mahomes in the wiki — his QB rankings aren't captured there. But I do have solid context on why Mahomes might be a fade candidate in 2026, and some other expert voices chiming in.
From the Patrick Mahomes page: The biggest concern is his recovery from a serious knee injury — he tore his ACL and LCL in Week 15 of 2025. While he's ahead of schedule and participated in OTAs, Andy Reid has been cautious about committing to Week 1, and the team even traded for Justin Fields as insurance. Mahomes' FantasyPros PPR rank is just 98 overall, suggesting the market is already skeptical.
Establish The Run noted Mahomes is falling in ADP (down to 92 overall), saying "I'm a little surprised Mahomes is falling given he participated in May OTAs just 5½ months removed from..." .
The Fantasy Headliners pointed to his weapon situation: "One name that I don't know if I would take over any of these names right now is Patrick Mahomes... just due to the minimal weapons at his disposal compared to the other guys on the list." .
So the fade case boils down to: injury uncertainty + a weaker pass-catching corps (relative to other top QBs) + a crowded backfield (Kenneth Walker III + Isiah Pacheco) that could tilt the offense more run-heavy. If Boone is calling him a fade, those are likely the drivers.