Historically, colonists/settlers/pioneers have had pretty appalling mortality rates.
Early settlers to the Americas had a very high chance of dying, with many settlements dying out entirely within the first year.
The high probability of death wasn't a secret; the colonists knew they had a high chance of being dead within a few months of arrival.
Yet they came by the boatload. Repeatedly, even after entire colonies collapsed, even after selling themselves to a near lifetime of indentured servitude to pay for the cost of their emigration.
It's a mistake to underestimate the horrors humans continue to undertake to live in a new place - whether it be immigration through deserts and war zones, stifling rides locked in cargo containers in deserts for weeks, refugees drowning on overcrowded, sinking ships, all the while risking criminal prosecution or racial or ethnic persecution... people go through situations with very poor chances of survival right here on Earth, right now.
Culturally, all of humanity is already used to accepting shockingly large number of people gambling their lives with slim chances of survival to live someplace new.
Lots of people will die trying, as we always have. It's difficult to see that aspect of humanity suddenly changing.