China have a bigger navy what if they put in the way and warn USA off and otherwise ignore it.
How would USA 'contest' and attempt to 'lift' the blockade? Try ram Chinese ships or start a shooting war?
No, China doesn't have a larger navy. They have more hulls but a lot of those are corvettes and frigates, total tonnage (or the number of missiles+aircrafts on active ships) tell a different story. What is more important, American Navy has centuries of experience refining its doctrines which the young Chinese navy lacks. Also, I was comparing to the USSR which had very modest navy in 1968, not to China
You want me to predict hypothetical events. I am saying that USA has steps to take which are far less drastic than declaring war. And sending its ships to Taiwan with "we dare you to try anything" message is a logical step.
non of that matter unless these step involve starting a shooting war, and yes many corvettes and frigates seem more useful to physically enforce a blockade than fancy aircraft carriers.
I suspect that USA would avoid any escalation over Taiwan (with which it have no longer a defense treaty) for the same reason you don't see NATO planes flying over Ukraine. Because if a shooting war does start, all it would take is one hypersonic anti-ship missile to sink an aircraft carrier for full blown war with nuclear power. Also keep in mind that China would be operating near its mainland with its air and missile force in range.
EDIT: This is a very different scenario from China invading, and USA engage in proxy war by providing Taiwan arms.