I am positive. Halacha does not recognize anything not visible to the human eye. A friend told me his Rebbe in a Yeshiva once told his Talmidim he believes it’s Assur to inhale through one’s mouth because he would breathe in microbes. That is laughable, ridiculous, and already mentioned by the earlier Poskim (turn of the 20th century) as being untrue.
But not being seen is not the same as not being visible. I believe the strawberry issue is that they are inside the strawberry, not that they are too small to see. If something would normally be visible or would be visible in different circumstances but just blends into its surroundings then it is still Assur to eat. The bug is visible so it has Halachic signifigance (i.e. is Assur to eat), it’s just not in a place where it’s visible. Bugs that are always too small to see with the naked eye have the same Halachic status as microbes-i.e. it’s as if they don’t exist.