It’s just lolita for the fashion style, gothic lolita is a substyle of the wider lolita movement which has other substyles like sweet lolita and classic lolita that each try to focus on particular parts of the overall aesthetic of cute, frilly, victorian-inspired clothing. The vtuber is very much not wearing anything even remotely lolita, the outfit lacks pretty much all of the characteristics beyond just vaguely being cute.

Ultimately the names for all of these call back to the novel Lolita, since in Japan the term became associated not with the pedophilia that is the focus of the text but instead it kinda merged with pre-existing idealised notions of cute young girls to the point where, over time, the term has been basically entirely disconnected from its source material.

Lolicon reintroduces the sexual component through the addition of ‘complex’ to the overall term. Technically there are non-sexual ways to understand it but like you said, it’s mostly awful pedo stuff. The vtuber here is specifically saying lolicon. (ロリコン is rorikon when transliterated)

Source is my obsession with lolita fashion and my little bit of self-taught japanese.