If you live somewhere where you have lots of sunny days all year long

I live in England so there's no guarantee of any extended period of sunny weather no matter the time of year, lol. Obviously it does get dark in winter though and that's what would tend to affect people. It's different when you're getting up in the dark and finishing work in the dark. For those who don't leave the office and don't have easy access to windows they might not see the daylight for much of the day if at all.

I don't tend to be affected though, my mood is independent of the season. It's more about my general state of health. If I haven't had a flare up for a while then I'm centred. If my symptoms are flaring up then my anxiety is through the roof. Depression is on the back burner most of the time but can come and go.

I live in Arizona, US and while it may be sunny all year-round, you can definitely still feel it when the seasons change. I personally have less energy during the later and early months of a year. The summers may be brutal in my area, but at least they're more uplifting.

Drop of energy from late July to (usually) early September - late August during the hottest months.

The cold doesn't affect me in the slightest, if anything I have more energies. Like, the will to move / run / cycle / etc. not to freeze.

I like all the seasons. Too long a spell of any specific weather is boring.