The music is like the bland, empty affect part of the Patrick Bateman character's outward personality, which only barely concealed the serial killer "depth" on his inside. Any edge in synthwave at all appears to be playing on this, where the smoother it is, the more meta and uncanny it seems, and with it the implication of extreme and bizzare hidden depths behind it. Like a David Lynch theme.
To me this makes synthwave perfect for the way millenials and younger people have had to manage their smooth social brand exterior in every concievable micro aspect of their lives, down to the organization of their bathrooms because it's all being competitively scrutinized for performance on video. When I hear synthwave, to me it is the soundtrack to embracing that insanity, which I don't have, but can appreciate.
Maybe people just like it, but that seems more insane than I'm really prepared to consider.