Does having too many pickups affect guitar tone, or sustain? Let's suppose a guitar has eight pickups while another one has just one of the same type. Would there be a tone difference, if the mega-pickup one was only using one of its pickups in a similar position to the single pickup guitar? Or would the effect of the extra pickups be too small to notice?
Well people do say that the magnetic attraction that the pickups have on the strings can reduce sustain. Ergo, more pickups = less sustain. Whether that effect would be noticeable is debatable.
I have to say my first response to the pic was: “how much hum would a humbucker buck if a humbucker could buck hum?”.
When I bought my tele the pickups were way too high. The stronger magnetic field killed the sustain on thickers strings and actually affected the frequency produced on the higher frets. I would assume that a wall of pickups would have a similar negative effects.
So, a pickup creates a magnetic pull on the strings, and this does have an effect on the way the strings are vibrating. It's an experiment you can do yourself: You can adjust the height of the pickup so that it gets closer to the strings. If it's close enough, you will hear a vibrato-effect when you're playing. Well, that's undesirable, unless you want to have vibrato everywhere.
So, if there's more magnetic pull on the strings, there's a higher possibility for unwanted vibrato; this could mean that you need to adjust the height, so that the pickups are lower (further away from the strings). Lower means a weaker signal/output; and the different strings might be affected differently, so this means different tone overall.
I have a guitar with a truckload of pickups. But I've never detected any vibrato - where the pitch oscillates up and down. Maybe this effect is not noticeable if the pickups are at a typical distance from the strings.