In my experience typically the power company is responsible for replacing the electric/telephone poles. If this is the case then it’s better to just have them replace the poles and keep the aerial cables since they probably won’t pay to to put them underground.
If you’re talking about the cables that come off the main poles and run to individual services that you’re responsible for then I guess it just boils down to whatever your preference is.
I just replaced 3 of these secondary poles that serve 4 lots each and hold the meter banks. It was about $1500-2000 per pole between the electrician, parts, and new pole. Since the main power lines down the road in the park are all aerial I kept my lines aerial too since it would not improve the aesthetic that much.
Also if you do go underground, you have to look at the cost of trenching, installing the bedding sand and conduit, backfilling with gravel and compacting, the impact to the roads and driveways if they’re paved, and all the restoration costs which add up very quickly. There’s no ROI on this and personally id do this as one of my very last projects if I had a ton of extra cash I wanted to spend.