There are many forms of oppression: sexism, racism, ageism, linguicism, audism, etc. through genocide, exploitation, dehumanization, control, violence, etc.
Oppression is defined in Merriam-Webster dictionary as "Unjust or cruel exercise of authority or power; a sense of being weighed down in body or mind".
Below highlights some common forms of audism. Many of them were practiced in the old days that are no longer allowed today; however, some of them are still practiced. Like other oppressed groups, Deaf people have experienced inequalities and social injustice.
Genocide. E.g. euthanasia and sterilization of deaf people during the Nazi war and sterilization after WW2.
Linguicism. E.g. forbidding signed languages for deaf students in schools; cochlear implants in deaf babies (who have not yet spoken out or made choices).
Violence. E.g. slapping a deaf child's little hand with a ruler for using sign language in schools.
Exploitation: E.g. physical abuses and sexual assaults in schools and homes.
Medical experimentation. E.g. cochlear implants; sterilization without consent.
Inaccessibility. E.g. denying access to proper healthcare; refusing to provide an interpreter.
Dehumanization. E.g. manipulating the natural (signed) language into signed English ("englisize") or other form which is a broken, unsystematic/unnatural language.
Despite those grim happenings, there are also positive resistance actions against oppression, such as Deaf President Now protest, and many other forms of resistance through literature, arts, books, lectures, policies, protests, and so on. Deaf people have been collectively fighting for human rights.
When you learn signed language, learn its culture and history, including oppression, hearing privilege, cultural appropriation, and so on. Learning ASL is not for your entertainment.
"If you are neutral in situations of injustice, you have chosen the side of the oppressor. If an elephant has its foot on the tail of a mouse and you say that you are neutral, the mouse will not appreciate your neutrality." -- Desmond Tutu (quoted in Unexpected News: Reading the Bible with Third World Eyes (1984) by Robert McAfee Brown, p. 19).
"We must take sides. Neutrality helps the oppressor, never the victim. Silence encourages the tormentor, never the tormented." -- Elie Wiesel in his Nobel Prize acceptance speech.