There is zero need for the PLAN to go fight the USN in the high seas.
The idea of the USN trying to cut Chinese sea lanes in the Indian Ocean are only the useless wet dreams of people who have zero idea of how modern trade works.
Modern trade doesn’t care about nationality of the ships, and all freighters and tankers pretty much work like segments of a conveyer belt.
That means the US will have no way to know where a ship is going if the ship files false papers, as would immediately happen if they tried a blockade.
The sheer volume of civilian shipping and the ubiquitous nature of raw materials makes it an impossibility for the US to board and inspect even a tiny fraction of the ships that pass through the Indian Ocean, nor would they get much actionable information even if they do board every ship since a barrel of oil is the same no matter if it’s going to China or Japan or anywhere else.
The only way a blockade could possibly work is through geographic proximity and bottlenecks.
That is why the US is so obsessed with the SCS, and why Obama/was actively encouraging the likes of the Philippines and Vietnam to go on a land grabbing frenzy there before China put a stop to that BS once and for all with its island building.
All of that was laying the groundwork to use the SCS to blockade China, as that is pretty much the only place on earth where it is actually possible to enforce a blockade.
In the event of a blockade, shipping bound for SK and Japan can swing around the Philippines to avoid the SCS while Vietnam can close its territorial waters to external traffic, and route their own trade through there with their customs able to legally intercept any shipping heading for China in their waters.
That would mean anything in the SCS would be either coming from or going to China, thus removing the biggest problem with trying to enforce a blockade in the modern age. Similarly, anything trying to loop around the Philippines and then make a dash for the mainland would easily stand out and make themselves easy targets.
Without its SCS bases, the PLAN would have had a hard time standing up to the USN in the SCS, far from land based support.
But those bases completely change the dynamics and now the USN has if anything, a tougher fight in the SCS than near Taiwan.
The islands and the PLAN needs to operate together, in a mutually supportive manner to be able to effectively counter the USN.
But as you can see from the remarks of Biden’s SecDef pick that they have still not given up on the hope of being able to blockade China via the SCS, hence their wet dreaming about sinking the PLAN within 72hs and thus opening the islands bases up for attack and invasion.