China would have a hard time trying to blockade from inside Taiwanese Territorial water, Taiwan have quite a lot of shore based Anti-Ship missile, and if Ukrainian Neptune can sink a Russian Cruiser (Unless you really buy the ship fire BS story), imagine those Harpoon, Hsiung Feng II/III Taiwan have can do to Chinese ship getting too close. In a blockade situation, you either need to shoot at US shipping or you just let them go and watch them resupply Taiwan.
On the other hand, it would be a great deal of damage to China even if US decided to do an Ukraine on Taiwan, unlike Ukraine, US will open everything to them, F-16, M-1 Abrams, M270 and HIMARS all will be open to transfer, and US have a lot of them in storage. Imagine US sending 400 F-16 to Taiwan? Or the 8 OHP Class Frigate that they have in storage? Or 1000 Abrams MBT? Or 10 Patriot Missile Batteries? All those Taiwan is currently operating, which mean zero transition time, and that's just what already have in Taiwan inventory, there will be talks for just about everything else, up to Arleigh Burke Class destoryer or even F-35 Stealth Aircraft if US think China is too far gone and going to invade, I mean, if they do, there are no point in withholding them just to please China.
If US think war between Taiwan and China is no longer avoidable, US will open up their National Guard Armoury and Arms Depot and tell Taiwan to come pick and choose, the difference between Taiwan and Ukraine is they already operate quite a few advance US tech, and probably more important than anything else, Taiwan can pay for those item they wanted, which make it a lot easier for Congress to allow the transfer.