If I am burning incense a few feet away from my laptop, can the smoke end up getting sucked into the system by the fan and screwing up the electronics?
It might - tars and resins from the smoke might interfere with the bearings in the fans, or might just create a sticky layer that will trap excessive dust.
Or it might not.
Screwing up the electronics - not directly. Indirectly, absolutely.
The smoke has some oils still, and other residues of burning (ash, some moisture, CARBON, etc) which can be sucked in by the fan on the lap(desk)top, and circulated around. Some will stick to things, as some starts to stick, more will stick, until there is a buildup of a film developing. That interferes with cooling a great deal, which can lead to heat-death (or performance reduction, if the machine has temperature induced speed reduction).
If carbon begins to accumulate, it can form conductive paths between the super-finely spaced conductors on the devices on the motherboard, which can result in almost any odd kind of failure.
Does it matter? That depends on how much is burnt, and how often, and if it’s being burnt while the machine is on. The primary problem here is the actual smoke, and what is included there. If you are sitting at your laptop, and you can smell the incense, then most likely, so can the laptop!
This is definitely more of a problem with laptops, since their cooling airflow is directed through very specific, narrow channels and very focused. It isn’t so much of a problem for desktops due to the much greater and freer (wow, that’s a funny looking word) airflow.
At the same time wouldn’t everyone who smokes cigarettes on a computer run into the same problem? So I assume/hope that is an engineering issue they addressed.
I finally refused to work on computers that were in rooms where people smoked. Everything gets covered in sticky tar. The fans do get messed up.
It is also best not to have a beard. My laptop started overheating and I asked my computer tech to clean it. He found the heat sink covered in little white hairs and asked if I had a cat (I don’t). But what I do have is a white beard.
Just don’t smoke marijuana while using the computer. That way you won’t even need the incense!