Kanye had tweeted about Trump in a positive light after the election. In December, the day he met with Trump in NYC, he wrote, "I feel it is important to have a direct line of communication with our future President if we truly want change."
Kanye also wrote about issues on which he felt he could influence Trump, writing, "These issues include bullying, supporting teachers, modernizing curriculums, and violence in Chicago."
Kanye's decision to remove the tweets was all his. The "Muslim ban" and other actions were the catalyst for his decision.