It potentially could be used to stop ageing no? Isn't it mostly caused by accumulation of cell damage?
Telomeres are also unimplicated in progeria ( https://en.wikipedia.org/wiki/Progeria ), which would be a serious problem if people thought aging was caused by loss of telomeres.
There are many factors to aging. DNA damage, that is not repaired, accumulates over the years. And then there are also damages to the tissue on the microscopic and on the macroscopic scale that don't fully heal.