They will, but burying and emplacing cables costs more and will destroy habitat across the emplaced area (land disruption is higher for underground than overhead cables). There is no alternative without any cons. It’s either that or do nothing and rely on current apparatus with more fossil fuel usage or just have electricity as a rich man’s commodity.
Voting Green to not mitigate climate change would be an odd one for their party, given they have slammed Labour for it or voting Green to make life hard for the poor would again be odd.