The gamepad merely supplements keyboard play, it doesn't replace it. And you don't need anywhere near 30 keybinds. Not even close. You need replacements for 1-5, Q, E, R, Z, WASD, Alt, Shift, Space, Mouse Movement, Mouse Scroll, Left/Right Mouse Click. anolog sticks handle WASD, mouse movement and scroll, and everything else is easily mapped to face buttons and trigger+face combos. Done. Other keybinds are for stuff like character sheets and inventory menus that can be accessed with a Main Menu button on the controller somewhere.
This is something that has been done successfully in other games before (FFXIV), and apparently by ZOS as well since there is a console version. I don't think the argument, 'It won't work' has much merit given the evidence.
I don't think this should be a controversial issue at all. I like keyboard and mouse, but sometimes I'd just like to chill out with a gamepad and not hunch like a zombie over a desk. The decision not to include gamepad support feels arbitrary to me, if not lazy or cheap.