I agree about the "just". You're right. It's about the same level of misleading as "scientific fact". People used to use "just a theory" to discredit relativity or evolution, exploiting the fact that the alternative terms like laws of physics or truth sounded stronger even though they weren't.

I still think it's harmful to general understanding to put any scientific knowledge on a pedestal of being unchallengeable fact. How can we know where we might be wrong? The earth is round, is it? What if that's just a slice of it in 3 dimensions and it's actually some other higher dimensional shape? Future people might laugh at our simplistic belief based on only seeing a little part of it - similar to ancients believing the Earth was flat because it was flat as far as they could see.