That’s why it’s such a hard problem. We barely have the language to talk about it. We have no way to observe it in other people. We have no way to measure it. And we have no idea how these things could even be done in theory.
These debates always leave me wondering if some people aren’t actually conscious. Some of these arguments wouldn’t make any sense to someone who actually experiences qualia. I liken it to the old debate over the existence of mental imagery, which was finally settled as being something that some people have and some don’t. But until that was figured out, the two sides just didn’t comprehend each other.