Jiang was a reformist who oversaw a successful opening and expansion of China’s economy, growing the country into an economic and political powerhouse to rival the US. Even after leaving office, he remained influential in China's success. His achievements should be commemorated.
Jiang repeatedly tried to justify the Tiananmen Square massacre, after which his government violently crushed all dissent, and he presided over the mass murder of members of Falun Gong. There’s no way to polish over the evil he oversaw — no matter how many economic and geopolitical accomplishments his government had.
There's a 50% chance that The Economist will rank China as a democracy in the Democracy Index by December 2100, according to the Metaculus prediction community.