I "think" I see a slight bit of dirt/dust in the snorkel in your picture , similar in place to the picture of mine , it looks to be damp with filter oil , but still present , so I think dirt IS getting thru the filter , remember , even a trace amount will still beat on the valve face , because whether you are putting in a bag of sand/dirt , or sprinkling it in 1 grain at a time , its still sand/dirt getting to the valves and getting hammered into them
As far as cleaning the carb , if you are not struggling with idling/low throttle bogging/stalling then chances are , it has not clogged the jets yet....however ..... I recently took my carb apart (fighting the same issue) , and found in the middle section (where the carb body splits) dirt to be present , as well as lots of it under the top cap where you access the slide and needle and all thru that part of the carb and all over the slide itself , I had to completely clean EVERY part of the carb , due to dirt/sand ...... Make sure you do not use carb cleaner on any parts that have O-Rings , including the fuel screw O-Ring , so make sure when you remove the carb for a thorough cleaning , to take care in removing ALL rubber parts , including the seal on the Slide Plate , and take note of its orientation , and how the slide plate sits on the carb (where the hole is in relation to the slide top/bottom)
I also found slight traces of dirt/sand in my gas tank , so after flushing it out , I now strain my gas with a coffee filter when pouring from one jug to another (I mix Non Ethanol with Av Gas , so I pour 2 different cans into one (smaller can) (I use Tuff Jugs , because of the gravity fill , it's just like a race can , no need to try not to spill using the typical hose type can when you can just tip the can upside down into the gas cap opening and when the tank is full the gas stops flowing and you remove it)
Anyway , you might look into the way you are oiling your filters , or possibly think about changing filter brands or filter oil brands/type .... I have tried them all (seriously all of them) and currently prefer No-Toil filters and oil ...and their customer service is second to none ..... and the best part .... I clean my filters with warm water (you can use cold if warm is not available) and Oxyclean , as the oil is water soluble , so no stinky gas or solvent cleaning , and you can literally stick your bare hands on the filter while cleaning it and then rinsing it , no bulky gloves , or mess to clean up , when you are done , you simply dump the dirty oil on the ground , as its enviro friendly , so no worry about disposal of used solvent , it won't harm anything in the ground ......... ok sales pitch over .....
Seriously , you need to look at why the dirt is getting past , as from what I can see in that picture , there is dirt getting thru ..... even the slightest trace amounts over time cause damage , and that is what I think you are finding , its not dirt dumping into the engine ..... its just being fed dirt constantly , like throwing powder into a fan , and that will cause the same damage as running no filter at all , it just takes longer to accomplish this ....