I love this podcast. The solo or very physics focused episodes go over my head sometimes but they're always a fun listen. I enjoyed "Jody Azzouni on What Is and Isn't Real" where they (among other things) argue about what it means for a thing to be "real"/"exist", and extend that to mathematical concepts, fictional characters etc.

I also found this one to stand out, but I don't remember exactly why: https://www.youtube.com/watch?v=oLKER6zFZ0A