I purchased the same dryer, and the sensor never consistently worked within the 1st 17 days. So I called LG, and the guy on the other end had a script in which he asked if I used dryer sheets. I said yes. He said then that the sensor wasn't working because I used dryer sheets and that the manual says I can't use them.
In fact, the manual says in the fine print, "Do not use fabric softeners or products to eliminate static unless recommended by the manufacturer of the fabric softener or product." It is the weirdest statement ever. It doesn't void the warranty. And that that statement also says that fabric softeners or static cling reduction products are in charge of customer use, not LG.
I also found this video at YouTube from LG -- https://youtu.be/DJxkCgLCpgc -- it educates the consumer on where is the drying sensor. AND!!! in the last few seconds (1:51) it shows a dryer sheet IN THE DRYER before clothes are thrown in. THIS IS FROM LG, showing you how to use the dryer.
Nonetheless, there are other websites online that do say that the microfibers of dryer sheets do have anti-static chemicals on them which can get stuck in the inner workings of dryers and degraded their efficiency over time or get stuck on sensors. We found the sensor and have wiped it with some alcohol to clean it -- nothing came off it. It was clean to start with. After all, we're only 17 days since it was delivered. But I suppose that if it were a longer time of usage, perhaps there would be residue there that we could have wiped off.
Within the inside of the dryer's duct system, however, it could potentially be a problem. But one would hope that your lint trap would pick up most of those fibers and any related 'gunk' so that it wouldn't be a problem.