iMac and dust

Hi all,

I have an iMac 27" and behind it, there is a plethora of cables and wires that have become very dusty and tangled since I purchased the computer in 2013. Would it be advisable to carefully clean the desk of dust and then do some nifty cable tidy tricks, in order to stop dust from accumulating? Or will dust accumulate anyway?

And, would this improve the performance of the cables themselves?

Thanks!