The bug

I can't get any Minecraft client to acknowledge a resource pack on any multiplayer server. It connects and displays all default textures with no prompt or error message, no matter if I set the server listing to "Prompt" or "Enabled."

This is similar to MC-58387, but the solution doesn't apply. The option cited is set correctly here.

I have a vanilla Minecraft 1.10.2 server (downloaded directly from Mojang) running on Fedora 23 with the attached server.properties, which references this resource pack (also attached). It doesn't work on either client (failing as described above).

I found multiple sources suggesting that mc.hypixel.net serves a resource pack, but see no evidence when I connect from either client, set to either "Prompt" or "Enabled." (It fails as described above.)

In the past week I've tried everything I know, and scoured endless forum posts. Never under any circumstances have I personally seen this work.

If it's not a bug in server or client, I'd love to know what I'm doing wrong.