Actually it does soften up for a few months every year. The issue is the damage caused by running cables underground in existing areas, and the cost.
Maintenance can also be a pain. Tearing out fences, yards, gardens, patios etc. Though I know they have tech now where they can auger vertically and don't have to completely dig up yards, but still have to dig it up if a cable breaks or something.
Actually how does it work for new underground deployments? The phone and cable drops have always been to each house so when someone wants service they just have to provision it at the central office. But for new services like fibre, the roads/yards are dug up and new trunks are run etc... but how does it work for day to day service deployments? Like months or years down the line a customer wants the new fibre service, do they actually have to trench all the way to the trunk line and splice for each new install? Or is a drop added to each house regardless of if they want the service, then if they do get it they just have to drill the hole in the house and run the rest?
We use a 3/4 inch PVC duct. So if the cable goes bad, we just pull out the old and pull in the new right behind it. If it's cut, it's easy to fix and fiber has splice kits now. Homeowners only need maybe 2 count fiber which is thin....at least for now.
We can't force a homeowner to accept. However they may be opted to have their service canceled if the provider wants to do away with the old cables...which typically doesn't happen for years down the road. This is currently future proofing more than anything else atm so they can opt to have it done later but at some point they may have to if the provider doesn't want to continue cost of old cables which are expensive to maintain too.
Usually if an old fiber is no longer big enough and they need to go larger like from 74 count to 200+, we either pull the old out of the ducts or put in new ducts, which they use larger ducts, usually 1.75 inch ( some fiber is still direct buried so no other choice but to add more). Some areas of easement is very congested, they usually buy more easement or we bore really deep.
Directional boring is the other method to get it somewhere without digging, plowing..etc. It has a computer chip in the head that augers as deep as you please and tells the operater where it's at, the angle, temp..etc. But it's very expensive. Used mostly to go under rivers, roads..etc.