Most Linux distributions have been working to slowly phase out i686 support as 32-bit x86 systems haven't been sold in large quantities in years and -- except for some niche markets in parts of the world -- most users out there are running x86_64 Linux. In reflecting the times, Fedora kernel developer Josh Boyer at Red Hat is working to gain support to make i686 a non-release-blocking architecture.
Fedora 32-bit builds would still happen, given community support and interest, but any bugs affecting only i686 wouldn't hold up Fedora releases from shipping. Josh recently had been dealing with an i686 bug affecting Fedora 23 development due to an upstream kernel issue, but this 32-bit-only issue had went unnoticed for about two months even though it affects any i686 user booting the Fedora installer on real hardware. When Linux developers are already stretched for resources, i686 just consumes more time for little return.
Boyer wrote in Validity of i686 as a release blocker, "Perhaps it is time that we evaluate where i686 stands in Fedora more closely. For a starting suggestion, I would recommend that we do not treat it as a release blocking architecture. This is not the same as demotion to secondary architecture status. That has broader implications in both buildsys and ecosystem. My suggestion is narrowly focused so that builds still proceed as today, but if there is something broken for i686 it does not block the release of whatever milestone we are pursuing. To be clear, I would support a move to secondary arch status for i686, but I am not suggesting it at this time... Making i686 non-release blocking would actually match reality. None of the Fedora Editions appear at all concerned with i686. Cloud is demoting i686 from its offering. Workstation has been fairly ambivalent about it and recommends x86_64. Server does the same. Given the lack of focus on it, and the fact that the broader community is not testing the development releases for i686."
Josh and other Fedora developers -- along with most Linux developers in general -- are only concerned about x86_64 when it comes to Intel/AMD hardware support. Other developers have already expressed interest in this proposal to make Fedora i686 non-release-blocking, but already there's individuals expressing interest still in it for their many-year-old systems that would want to upgrade to the latest Fedora...No decision has been reached yet but you can check out that linked mailing list thread for the latest comments.