I am also one of the Bitcoin supporters but I do not think that life would be much harder if they have not adopted Bitcoin. Remember in this situation, a person's life that has not adopted Bitcoin and remains not adopting Bitcoin, there is no change in occurrence in their life. They will continue their life as they intended it to be. The only thing here is that they are missing out but their life is still the same living without adopting Bitcoin.
Internet and Bitcoin are two different entities, you cannot go online without the internet but a person can still purchase things, or invest in a venture even without participating or acquiring Bitcoin.
Your explanation makes sense when you talk about this kind of scenario to the unbanked because Bitcoin has given an opportunity to the unbanked to participate in the global economy. So I guess this kind of explanation is not applicable or effective to everyone.