Forgive me if I make some blatantly obvious statements here, I'm just thinking aloud, putting my own thoughts in order re: Taiwan.
The status quo whereby Taiwan is not a declared or recognised sovereign state, but in practice enjoys most of the characteristics thereof, reflects a trilateral balance of power and interests between the PRC, ROC and USA. No party has been entirely satisfied with that status quo, but each has preferred it to the alternatives on offer.
In recent years, however, the set of interests and considerations that have previously supported this trilateral status quo have been progressively undermined by each party to the triangle.
The PRC's growing military strength increasingly tempts Beijing to fulfil its ideological commitments and "resolve" the issue of Taiwan by force, while ongoing economic development, including reorientation of the economy to one based upon domestic consumption, leads PRC officials to look upon the costs of such a path with less horror than before.
Under the DPP, the ROC's commitment to the status quo is also undermined, in that a powerful faction within the DPP is ideologically opposed to the foundational idea that supports the status quo, i.e. that Taiwan is indeed part of China. Alarmed by changes in the material balance of power between the ROC and PRC, and emboldened by commitments and expressions of support from putative allies, the ROC under the DPP is thus increasingly tempted to move from de facto to de jure independence.
The USA's commitment to the status quo is fundamentally premised on its desire to maintain a working relationship with the PRC. This was originally a strategic imperative, seeking to exploit the Sino-Soviet split to undermine Washington's principal strategic adversary at the time, the Soviet Union. Following the end of the Cold War, the strategic imperative for maintaining a working relationship with the PRC collapsed, but the relationship continued to be supported on Washington's end by an increasingly strong economic imperative. American corporations, always intimately connected with power in Washington, sought both access to China's vast domestic market, and also to exploit China as a low-cost manufacturing hub to enhance their own profits. As China's economic and technological development has proceeded, China's own corporations have progressively "climbed the value chain" to increasingly challenge Western commercial leadership of sensitive fields, exemplified most clearly by the saga of Huawei and 5G telecommunications infrastructure. The trend over time in Washington has been increasingly to see China as less of an opportunity, and more as a threat, to the point that the relationship today can be described, uncontroversially, as nakedly adversarial. Washington's diminishing commitment to maintaining a working relationship with the PRC increasingly tempts it to undermine the status quo with respect to Taiwan, as for example by abandoning "strategic ambiguity" as a check on the ROC.
Mainstream western discourse takes it as read that the PRC is chiefly if not solely responsible for undermining the status quo with respect to Taiwan. As illustrated, the material conditions that support the triangular status quo are in fact being undermined at all levels. Indeed, I believe that a compelling case can be made that it is the interaction of the USA-ROC axis that is most profoundly destabilising to the peaceful status quo that has prevailed these past decades. An increasingly ambivalent if not antagonistic or indeed nihilistic Washington establishment increasingly emboldens the DPP to make good on its ideological commitments, in turn occasioning increasingly sharp rhetoric from the PRC that results in further deterioration of relations and ratcheting of tensions under the classic paradigm of the "security dilemma".
