In my headcanon, the Johto games take place in mid-Fall because of images like
>>34828125 No harsh environments like in Sinnoh, Hoenn, Unova, and Kalos, not too mountainous like Kanto, and not too tropical like Alola.
There's something soothing about the blue and greens of night time, and the fact that buildings all have little yellow lights on made the world feel like it actually has people living in it. Days of the week mattered for the weekly siblings, Pokemon and people had schedules, bug catching contests only happening on certain days of the week, etc...
The fact that HGSS brought back companion Pokemon to add to the immersion is just... the best.
