I dunno. Even at the peak, that’s only a third of the day alone.
And if you look at the other graphs to see what’s providing the slack, it looks like (disregarding the youthful peaks) quality time with friends, family and partner all hold steady throughout (or even climb a bit, in the latter case). What falls off is time with children (which is natural as they leave the nest), and time with co-workers (who needs 'em).
So maybe what’s happening is as the time demands of work and child-rearing ease later in life, people are simply choosing to spend most of the time windfall on ‘me’ time (and the rest on partner time) rather than anything else. Which would be a positive, at least to the extent that it’s really voluntary.
The sad part is really that sudden droop in ‘partner’ time at around age 70 - because presumably that’s mortality rather than voluntary separation.
