PRC already assumes mainland strikes, and TBH this has been default assumption for any US adversaries because US has projection capabilities and therefore homeland attacks must be accounted for. US warplanners and politicians haven't been shy about talking up striking PRC mainland, whether they seriously believe so, or whether it's all security theatre to create security delimma for PRC. Never the less, it's baked into the consideration for PRC - what hasn't been considered by US planners and populus are substantial CONUS attacks, because up until now geography has shielded US, but long range strikes / advanced rocketry makes it possible, and adversaries will match escalation when they can. It's only up until recently, US adversaries technically couldn't strike CONUS even if they wanted to, barring desperate propaganda measures like fugo balloons. And it makes escalatory sense since so much of US power/influence depends on CONUS serenity. A world where CONUS is vunerable is a world where others forced to "derisk" from US and reevaluate viability of US security commitment.
As for allied ports and rear support, US basing that enables operations against PRC in theatre, which basically US force structure requires at this point (hence all the wargames trying to convince JP to distributed basing), is IMO even more forgone. Various US partners signalled they wouldn't directly contribute to TW war but will provide rear support, but that's enabling US war regardless, so very likely they're going to get glassed. PRC systems confrontation and system destruction warfare is structured around destroying the softer/easier targets like support ships, tankers, ISR infra etc. Hitting them is doctrine. And ultimately, it's in PRC's long term interest to destroy as much US forward presence as possible, because that's historically how outside hegemons get kicked out, through sufficient force to demonstrate their strategic posture is no longer viable. And US having decades of build up abroad has more dependencies and more to lose if their security architecture becomes unsustainable.
As for unsupported carrier operations, IMO if you consider the sorties numbers their effects are close to negligible. Boat might be nuke powered, but there's only enough supplies (fuel/ordnance) for low hundreds of sorties, 50%+ of which will be buddy tanking / support due to how far PRC A2D2 has pushed standoff range, which leaves a even lower 100s of actual hitters. Assuming no interceptions. Barely enough to dent the 100,000s of targets from mainland. It's not that US CVGs are weak, just PRC operates on another scale, more targets, more concrete, more counter measures etc. Without constant replenishment carriers become single deployment assets with limited use and cost:vunerablity ratio not in their favour. And even then nuke propulsion need to return to dock, where they can be promptly hit with global strike.