It doesnt work that way, boobycibo. There is no good or bad evolution. It is just the adaption to the environment.
First of all, obviously you are talking solely about the tiny fraction of the human population able to access asthma treatment. Unlikely to make any significant impact on the race as a whole.
Secondly, other traits will be adaptive. For example, people who are resistant to diet induced cancers will probably have an evolutionary advantage. People whose systems are better able to withstand pollutants. And so on. People better able to withstand uv exposure and the accompanying degradation of folate.
In 10,000 years, I would suspect that those of us most susceptible to pollution, preservatives, etc will have died out.