Yes it will kill you. Everything will kill you.
Life is a terminal illness and you are heading along that little conveyor belt and into the abyss eventually whether you use subscribe to x y z or avoid x y z. The question is – what things kill you less quickly?
Early retirement does get some bad press by those who claim that humans are poor simple souls that are lost without the reassuring shackles of paid employment and management surveillance. Decades of routine, following instruction and having the majority of the week accounted for will provide a level of comfort. If that structure is suddenly removed and not replaced with something else, then yes that is going to create a problem.
(As an aside, I would hazard a very unscientific guess that the grinding stress of money, and decades of ongoing job pressures would overall have a much greater inflammatory effect on the world’s humans.)
The distinction is this – Lack of purpose, lack of engagement with life and gradual atrophying of the body and brain (through lack of exercise or mental activity or both) is deadly. Use it or lose it toots.
People who retire and promptly decide to turn into living vegetables with no direction or desire to learn, create or get better at anything, will of course be more likely to die early.
On the flip side, people who retire (at any age) and revel in each day, using the freedom to make themselves and the world happier will surely live longer.
If money is removed from consideration – then work becomes whatever we decide to put effort into doing. We just get to choose to work for fun.