Exterior house corners aren't filled in. Do I need to address this?

Hi HI. I'm making preparations to paint the exterior of my house, and I have these corners that are not filled in where they meet the siding. I'm not sure if I should fill these as I've read different things about air circulation. The siding is cedar, and the corners are also wood. Should I fill these? And if so does anyone recommend a process? I live in the PNW. Thank you for any help!

Here is a picture of the corners: https://imgur.com/pyWBWUV