I wonder just how much air power and drones are going to play a role if it is anything like what's happening in Ukraine.
The Taiwan strait is 110 miles. That's a LONG way to be exposed to fire. They'll have no protection against kamikaze sea-borne drones that could be self-guided in a high EW environment and launched from civilian fishing boats but they could be thwarted by noise makers or blinded by smoke screens.
Even if they establish a secure beach head they'll have to be very creative in logistical supply for munitions, heavy equipment, and personnel and the evacuation of the wounded.
There is no guarantee as to how well the Chinese troops will perform but they will not be motivated more than the Taiwanese. Both sides will most likely start running short of ammo in a few months of heavy fighting.
I doubt if the Japanese and Guam bases would be totally destroyed. That's a lot of dispersed areas to destroy unless they plan on using nukes.
Chinese amphibs: link
Then again, the Chinese are tricky, will have the initiative at the start of the hostilities, and most likely have some asymmetrical tactics up their sleeve like insurgents that take out key positions before the invasion or detonate EMP devices near command nodes, chemical/biological weapons, or the scare of a pandemic to panic the civilians, false flags, internet PsyOps, the possibilities are endless.
The Chinese could also deploy remote control concrete submarines that lay at the bottom of the ocean at choke points with passive sensors to fire rocket-propelled torpedos against submarines and surface ships. These would be extremely hard to detect and fairly inexpensive. So could Taiwan.
Wolfhag