This looks to me like a street tire being used on unimproved roads.
I note that the tread pattern seems to point to "Street Only". It might be nice if we knew the actual brand and tire line to help us diagnose that part of it.
The second part is the comment about working construction sites. Some construction sites can be "paved" with gravel or small stones - and not only would those be fresh and still sharp-edged, the road itself might be bumpy, which would add to the condition.
Front tires? Could be from sharp turns or hard braking.
I should note that I have seen this condition on tires used on aggressively paved roads, where the aggregate is kind of sharp-edged. I've also seen this on tires that have low rolling resistance, such as OE tires.
Do you need to remove the tires? No! - at least not until the chunking starts to reach below the tread pattern and into the undertread. If it starts to reach the steel belt (or the nylon cap ply) replace the tires immediately.
Rotate tires? That will likely help even the process out, but since the cause is the road surfaces (if I am right about that), then it will not eliminate the condition.
I note you are in Italy, and the one thing I noticed while I was there was the use of basalt rock as a paver - not only in a cube form, like brick pavers, but also as crushed stone in bituminous pavement. Basalt is extremely hard, which makes for a good wearing road surface, but it can chew up tires when new, and takes a long time to wear the sharp edged off - and then it gets slippery when wet.
The other thing I noticed was that straight roads are almost non-existent. If you normally make lots of turns, this will make the situation worse.
Ultimately, you need a tire better suited for your conditions.
