Polymarket's new advertising campaign starring LeBron James and featuring Sue Bird has drawn sharp criticism on Reddit and in opinion coverage. A thread in the r/wnba subreddit received 228 votes and 99 comments criticizing the athletes as sellouts. Houseofstrauss.com compared the backlash to Polymarket's broader public hostility versus DraftKings, citing a critical comment from NBA gambler Haralabos Voulgaris. The campaign nonetheless drove Polymarket past rival prediction-market apps on the App Store download rankings.

The backlash tests whether celebrity endorsements can convert to retained users when the celebrities themselves become controversial. Polymarket paid for star power to normalize event contracts for casual traders, but the r/wnba thread and Voulgaris criticism show the same fame can activate hostile audiences. For a platform fighting state attorneys general who want event contracts reclassified as gambling, every public fight that frames trading as exploitative weakens its political position. DraftKings now watches whether its former endorser becomes a liability for the rival that took him. Polymarket's next marketing choices carry heavier creative control costs, and competitors with stricter partner guidelines can cite this cycle to advertisers weighing platform safety. The campaign's real measure is whether download spikes survive the reputational drag.