I remember in early(ish) Linux, the terminal programs had a setting to be at least partly transparent, so your desktop background (and other windows? I forget) could show through.

Wound up constraining what desktops you could choose, and how you had to set up your terminal colors. And since I prefer dark text on a light background, it didn't work for me from the beginning.

I imagine those programs still have those settings, but I don't see that behavior in screen-shots of programs any more.