I believe by "'big woman' boom", the artist means a very recent trend on Pixiv to post pictures of ใใซๅฅณ, unusually huge women. (I think the word is read as DEKA-onna, literally "deca-woman", as in the metric prefix deca- for multiplying by 10.) This Pixiv page explains the term, and post #7638840 (a KonoSuba reference) pokes fun at the trend.
Young Hoshino: "You are the student council president of Abydos, are you not?!" Young Hoshino: "How about you be a bit more self aware of the responsibilities that you have, for once?!"
Present Hoshino: "Really... what an awful kouhai I was..."
Also, "Memory Tour" seems to be a reference to a certain part in Attack on Titan? If anyone else's familiar with it and you think this post warrants the copyright tag, then please do so.