I too use a laptop in my main system, no isolation as it just sits on a glass shelf. An external hard drive where music files are stored is connected to the laptop. No complaints so far.
I have isolation for all my other equipment and speakers.
The OP raised a legitimate concern, i.e., the annoying fan noise. I use Dell XPS as a music source. A while ago the fan came up constantly and, without 2nd thought, I put the isolation feet underneath hoping the fan will quiet down epecially when music is playing. It turned out the CPU was occupied by some resided app. in the background and caused the fan to operate endlessly. So my advise is, as the first thing, to check on the CPU and eliminate unnecessary bagages. Whether adding isolation feet as a damper helps vibration attenuation is debatable. To completely cure the root of the problem, I will suggest the use of fanless Mac instead.