Bill Simmons withdrew his NBA MVP vote because he had gambled on the outcome, which was a conflict of interest. Simmons bet that LeBron James would win the MVP and, not surprisingly, he voted for LeBron James.
From ESPN PR via email:
“Bill had never received a ballot before and didn’t find out he had one until two-thirds of the season had passed. By that time he had made multiple MVP bets, two of which he had discussed on podcasts. He ended up withdrawing his MVP vote to avoid the perception of any conflict.”
Simmons placed his bet before he knew he had an MVP vote. Not sure there was sinister intent here, but media privileges come with media codes of conduct. Guessing anyone else would be facing a lot more flack for this.