Yes, it means we’re moving into Demure Autumn or even PSL Time, but it also indicates seasons themselves are getting warped by meme culture.
https://www.wired.com/story/the-end-of-brat-summer-does-not-mean-what-you-think/
https://www.wired.com/story/the-end-of-brat-summer-does-not-mean-what-you-think/