Yeah, this could work if your bindings are separate and the spoiler lever is completely stationary without any movement at all. But if you get any small vibration that made the spoilers move even slightly, it will start to feed into the sim with the axis position.
The way that I bind my autospoilers was to actually arm/disarm the autospoilers using the spoiler lever itself. Like a Boeing, you arm your autospoiler by pulling the spoiler lever back one position, and disarm by pushing it back to retract position.
This won’t work because when you assign the lever to an axis, and you pull the lever to “arm” the autospoiler, the axis position will always override. This is easily noticeable because when I look at the wings, and I pull the lever to the arm position, the spoilers actually open a little bit (about 25%) and it stays.
So my method of actually removing the spoilers axis is so that I can arm/disarm or retract and deploy spoilers in the exact same way as using Boeing. Where I can use the same spoiler lever to do all of them. Not to arm/disarm with a separate button which is not representative of the behaviour in the real aircraft.
One other way that they can do to fix this (if it hasn’t already) is to introduce a deadzone at the end. I know there’s a Extreme Deadzone, but I haven’t had a try if this works yet. The idea of this extreme deadzone is so that the sim can “ignore” the inputs of the spoiler axis for the first 25%, so we can freely arm/disarm without the spoilers axis being triggered to override it. Only when we move it passed the arm position, the spoilers axis start feeding into the sim.