I actually agree with his philosophy (for the most part) and I too, share similar sentiments too. I do not wish to live to old age and suffer through decades of decline while spending exorbitant amounts of money just to sustain (a shitty, low quality) life. I also do not have another SO (significant other) nor dependents (children or people that I am legally responsible for). Furthermore, the thought of being dependent on others terrifies me more than death itself and I have seen the elderly suffer through (granted, some were still happy to be alive and more power to them, but not for me). That is not something I would want to go through.
The moment life becomes too hard and is going to continue to decline would be when I check out, barring the fact that I don't die before reaching old age; all depends on the circumstances at hand, health, time, and a few arbitrary factors.
@Carma interesting philosophy and he is also quite a deep thinker too. He approaches life from a pessimistic point of view thus death, being the neutral state would be a positive state to ascend to.