They're not? They immediately walked back the comments, warning against market bubbles today and having the state pensions sell equities, clearly signaling they don't want to create a 2015.
That said, their goal is to create an SPX-like (or NASDAQ-like) capital market system that is stable, low volatility, invest-able with a good return profile for international and domestic investment.
The problem is it's easier said than done, and given the lack of liquidity and retail non-institutional dominance still of the domestic market, it's hard to micromanage like that. But as with all things in China, CCP wants to control not just the direction but the speed of change!