Comparative advantage shows that production in either countries is improved, increasing supply and therefore putting pressure on prices, increasing the purchasing power. This simply isn't redistribution of income.
An individual worker, whose livelihood is destroyed and who is unable to perform any other form of work (unlikely, but conceivable) will of course have less than before. I don't see anybody making the argument that every single individual will be better off (that's obviously wrong), but the purchasing power of every individual income will increase.
You can make an argument that such inequalities should be mitigated by some income-redistributing measure or another, but that's orthogonal to comparative advantage itself.
An individual worker, whose livelihood is destroyed and who is unable to perform any other form of work (unlikely, but conceivable) will of course have less than before. I don't see anybody making the argument that every single individual will be better off (that's obviously wrong), but the purchasing power of every individual income will increase.
You can make an argument that such inequalities should be mitigated by some income-redistributing measure or another, but that's orthogonal to comparative advantage itself.