My family live in a coastal area very popular with tourists.
Many of the quaint cottages are now second homes. Where these are rented out as holiday cottages they provide year round income for the local economy: shops, tourist attractions, jobs (lettings, cleaning, maintenance).
Where they are empty they have indeed turned the High St into a dark dead zone in winter.
But locals have either moved away to seek more lucrative employment in cities, or sold their cottages to live in more spacious modern new builds, with a drive.
Locals live in the 1950s council houses beyond the playing field, or in the 60s bungalows and semis on the other side of the main road. Not in the picturesque bit.
None of my parents' neighbours have adult children who have stayed in the area. All gone to London or the Middle east (oil) to work.
Coastal and rural deprivation is real. There is very little public transport, the hospital is bloody miles away, jobs are dwindling. Houses are falling off the eroding cliff in one nearby village, while others will be underwater within a few degrees of global warming.
The village's problems aren't mainly caused by second homes, not by a long chalk.