The engine has suffered from dirt, but in dirty engines with no other faults the bearings exhibit pronounced wear in a band in the centre of the bearing where the oil hole is. This is where the dirt first comes out into the bearing and causes the damage, your bearing wear is across the full width of the bearing which suggests there are other issues such as low oil pressure caused by incorrect clearances and/or oil issues as well as dirt.


[Linked Image from rttech.com.au]