Rob Schneider is considered "blacklisted" primarily due to his controversial opinions and actions that alienated many in Hollywood and the public. Key reasons include:

• His outspoken anti-vaccine stance, which led to significant backlash and lost opportunities, such as State Farm pulling a commercial featuring him in 2014 due to his anti-vaccination views.
• Making offensive and inappropriate jokes, including those targeting women, transgender people, and ethnic groups, which led to him being heckled, booed, and even escorted off stages during live shows.
• Publicly sharing conspiracy theories and opposing COVID-19 measures like masks and vaccines, further damaging his reputation.
• Negative audience reactions in comedy performances, often involving walkouts and widespread social media criticism.
• His controversial behavior and statements have led to him being largely excluded from major Hollywood projects outside of Adam Sandler's movies.

Despite this, Schneider himself has stated that he feels "emboldened" after surviving this backlash, but the general consensus is that his career suffered a significant decline due to his remarks and beliefs.