The biggest argument against increasing the state pension age has been because it impacts the poorest most IE those whose only source of income when they give up work is from the state. This is further exacerbated by the fact that these very same groups are less likely to experience as great an improvement in life expectancy as the rest of the population. Traditionally women have retired at 60 and men at 65 which means couples are able to enjoy retirement together from as young as 65. In the future,with the equalisation of state pension age at 66, this will mean for many couples, where the women are often younger, it might be 69 or 70 before they retire together as a couple.
This provides opportunities for services targeting the men who may be at home for several years while their wife works ie a reversal of the current position. It also suggests that employers need to consider providng sabbaticals/gap years/flexible options/ R and R, for people so that they can refresh and enjoy time off together long before they're both in their 70s.