Same for me, has been my whole life. I complain about it all the time. It's well documented that people can read black on light far better and with less eye strain than light on black; yet there seems to be a whole generation of developers determined to force us all to try and read it. Even the media sites like Netflix, Prime, etc. force it. At least Tubi's is somewhat more readable.

Sometimes a site will include a button or other UI element to choose a light theme but I find it odd that so many sites which are presumed to be designed by technically competent people, completely ignore accessibility concerns.

The most common mistake I see (on this website at least) is the assumption that one's programming competence is equal to their competence in other things.