True, but he never said he was communist in the first place. Nor would he be able to claim he is one even if does have communist party membership, since as a CE, you are not technically allowed to have a particular party affilation.
In any case, what the CCP strategy is in Hong Kong has nothing to do with communism as Karl Marx would understand it. The CCP's "united front" strategy has always been to ensure the power brokers in Hong Kong, the business elite, are allied with them. In return, the CCP will protect these elite's interest. That is why you find a HK government (and implicitly Beijing) as the protector of the rich in HK. Now that would be anything except communist.
Why?
When this united front strategy was first devised (in the 80's), the business elite indeed was the key to HK's wealth and stability. Therefore, to protect investor confidence in Hong Kong after the handover, the CCP naturally sought to reassure the elite that their business dominance would be safe.
However, the problem with this strategy was that since the handover, HK society has changed. The upward social mobility that characterize HK's rapid modernization in the 60's, 70's and 80's has gone. Whereas before, even if times were tough (and they often were), so long as you worked hard and put in the effort, you will have a decent chance to improve your circumstances and enjoy a reasonably good standard of living. Now however, the young people here find that increasingly, no matter how hard they work, they will not be able to obtain that elusive apartment. They are trapped in poverty forever, essentially.
And part of the reason is that the business elite that was once responsible for the upward social mobility has become the barrier to it. They monopolize many key industries in HK. There are few opportunities for new businesses to breakthrough these barriers to entry. The government has been oblivious to it. And so has Beijing. Their strategy has resulted in a polarized society of tycoons pitting against the poor youngsters. But the CCP either can't or won't change this out-of-date policy.