Why is there no Big Sur support for iMac (27-inch, Late 2013)?
Is there any particular reason for Apple not supporting Big Sur on 2013 iMac's? Can I hope for support in the future?
+1. 2013's last updates are Catalina 10.15.7, they will not be able to go beyond Catalina.
Apple did not publish the hardware limitations 2013 and earlier iMacs have that limit them from upgrading to Big Sur. While your iMac cannot upgrade to Big Sur it will be still be updated with security updates periodically and is completely useable.
If you have a specific need for Big Sur then well it's time to upgrade to a newer Mac.
