Engineering new biomes for fun is different than having to do it every year or you die.
What do you do when seasonal heat makes Pakistan and India uninhabitable for large parts of the year? We're not prepared for that kind of migration, we didn't even deal with Syria well.
Farming and other activities often require decades to truly show a profit. When rainfall patterns are changing on short timescales, you will not be able to plan for food production given the underlying churn in fertile locations.
What do you do when seasonal heat makes Pakistan and India uninhabitable for large parts of the year? We're not prepared for that kind of migration, we didn't even deal with Syria well.
Farming and other activities often require decades to truly show a profit. When rainfall patterns are changing on short timescales, you will not be able to plan for food production given the underlying churn in fertile locations.