Just some additional comments. This appears to be prior to the meters so chances are it is being used for service taps. What you see here is not technically a “gutter” as it is more a “wireway” but alas basically the same thing.
Later (current) editions of the NEC require that tap to be shielded or insulated from potential touch hazard but probably not required at the time this was installed. Also in terms of the ratings, you have to remember that not all jurisdictions adhere to code rules precisely the same way so with that said if you notice abnormal rust, lack of wireway bonding and so on…defer it as you did and let the Licensed Electrician sort it out.
Continue to do your review and note all that you are concerned about. However, remember it only takes one issue to defer for evaluation by a specialists (you are a generalist) as other hidden issues could be found.
Again I did not examine the image so other issues may be present. In a perfect world it would be rated for it’s environment but not always and you can also mention it (saves your butt on that part) but since it has been in service for quite some time…defer it , make comment on it and then address the other issues.