Hello!
Yes! People should make changes to chemical compounds.
The essence of Chemistry is the change. Chemistry studies matter and the changes it experiences. If there wasn't change, Chemistry wouldn't exist. The job of a Chemist is to study the changes in chemical compounds, how do they happen, and what applications those changes might have.
For studying changes, it is necessary to change the chemical compounds, so yes, people should make changes to chemical compounds, to understand them better and for the sake of Science.
Have a nice day!