Your essay can be improved both mechanically and substantively. First, the mechanics:
I would strongly suggest against telling the reader what you cannot do in your initial paragraph. Keep you purpose positive.
Please be sure that you provide specific examples to support your statements. For example, what factual evidence do you have that living standards have improved in the last thirty years? You do say that 'we' have access to technology, that 'we' eat better, etc. Who are 'we'? I am afraid that, the claim in your opening sentence notwithstanding, many people could argue the point.
You come close to saying that, while having money can make life easier for people, it is not a direct causative factor of happiness. This would be a good point to develop.
Again, if you are going to say that 'we' are spoilt and haven't had to endure the same hardships as previous generations, be sure you state the population you are referring to. This statement is far from true for people is many parts of the world.
So, to sum up, be positive about your thesis, clear about your references, and sure of your claims.
I hope this is helpful,
- For Teachers