As a lineman for 40 years I can tell you there are poles everywhere that woodpeckers have made nests in. (yellow jacket nests are worse) You couldn't stop it if you tried. Also I can tell you we don't inspect poles on a regular basis not enough time in the day to do that. Only when we are working in or upgrading an area. Kinda like a lady that was upset because we didn't know her street light was out for 2 weeks until she called us. Thought we should be able to keep track of every light in town without being called. Lol! The first time I saw a ton of woodpecker damage was in southern Illinois after their inland hurricane. Brand new high line with holes everywhere. Their fix was they filled the holes with expandable foam.