China now has an America-style amphibious warfare ship:
The Type 075 is a landing helicopter dock ship, or LHD. LHDs are large ships designed to hold a marine landing force and the transportation needed to get them ashore. LHDs have a large, full-length flight deck, similar to aircraft carriers, to launch and recover attack, observation, and transport helicopters. According to Naval News, the Type 075 is rumored to be capable of carrying up to 28 helicopters.
Remember, we have the capacity to lift just two brigades at once. And the Marines are rethinking amphibious operations in the face of persistent surveillance and cheap precision weapons in the hands of enemies defending the shores.
So China's commitment to those big ships is kind of odd, no? They are building these ships just when they are most vulnerable to a peer's military with the same kind of weapons China has fielded to defeat them?
Let me remind you that China doesn't have a monopoly on those anti-access/area denial (A2/AD) weapons.
I think these ships and the growing Chinese marine corps (building toward 6 maneuver brigades, I think) is a red herring as far as Taiwan is concerned. The marine corps is intended for power projection against small powers and not amphibious warfare against major opposition.
While marines could help against Taiwan, I don't think they'd be critical to success and nowhere close to being the main force in a Taiwan scenario.