Whatever else it is, To Paradise is certainly something. It's got a texture and heaviness that feels similar to A Little Life, and I found it at once boring and somehow compelling - at least until the dystopian final section, where the pace picked up a bit at the same time that it shifts to a nominal main character who is definitionally diminished in affect and even harder to relate to than all those who came before her.
That heaviness extends to the prose and scene- and chapter-level structuring, which I wouldn't call elegant. There's an awful lot of what feels like redundant detail - admittedly especially in the first, 1890s-set section, where the detail is possibly period-appropriate for literature of the era - and some pretty thudding expository stuff, especially via all the letters.
Having said that, the novel as a whole does land as more than the sum of its parts, in a way that doesn't feel over-determined despite the overt formal signposts - the 100 year leap-forwards, the building on Washington Square, the recurring names (and suggestion of a familial connection near the end). Each of the three sections - the David Bingham of 1893 and the possibilities of Edward Bishop, the David Bingham of 1993 and his relationship with his Charles along with the layering of his father Kawika's own story starting some 50 years earlier or maybe more, and Charlie in pandemic-struck 2093 along with the layering of her grandfather Charles's story again starting some 50 years earlier - is more satisfying in the context of the others, the lack of individual resolution in each of their endings especially. None of them are truly stand-alone, despite the near-complete lack of any real story crossover between them.
Scattered throughout are some powerful scenes and motifs - the first Charles's (the 1890s David's older suitor) experiences in Canada, the failed dream of Lipo-wao-nahele, the horrific fate of the two unwell children in their plastic-sealed confinement. And also a set of powerful themes and visions about humanity and the more visceral and sometimes darker desires and social and political forces that drive it - including abuse, need, power, control, privilege, family, love and loss.
It's impossible to not read To Paradise at least partly through the lens of COVID-19, and what's less clear is to what extent the novel's primary focus is ultimately around both that real-world pandemic and the imagined series of catastrophes leading to its dystopian authoritarian vision of a future America, as opposed to those being rather illustrations or manifestations of a broader thesis about society and human nature. And equally unclear is the ultimate relevance of the embedded queerness - embodied almost entirely through seemingly cisegendered homosexual men - that is part of Yanagihara's imagining of these alternate Americas.
In the end, there's a lot of grist for the mill there, and while the heaviness can at times feel heavy-handed - and, somehow, opaque at the same time - and I didn't find it a particularly satisfying reading experience as a whole, To Paradise is certainly an achievement, at a minimum in putting these big issues into conversation in a way that illuminates, rather than merely illustrating.