The human lifespan is pitifully short at present. If our life expectancy was, say, a million years a journey which took ten thousand years would only be 1% of our life. At present, 1% of a human lifespan corresponds to 9 months or so. Many people have embarked on journeys with that amount of travel time.
It might be easier to take the slow (100km/s) approach than the fast (200,000km/s) if medical technology progresses faster than its transportation equivalent.