When you see questions with a physics tag on WB, lots of comments and answers (and closures) immediately start to assess correctness, with current Earth physics as a reference. When a science or reality tag is put, the fact-checks are even more prominent.
I wonder if peer-mods have the expertise to judge physics questions this way. And often, there are nice engineering ideas that end up in closure, because they are qualified as bad research, insufficient focus, or off topic. I think it would be more WB-like, if the "physics" tag would be split into "physics-past" and "physics-future". This avoids questions that better be put on physics.se, and it allows a fictional approach to physics, without having to assert scientific thruth all the time.
A physics-past tag will be about science and technology for the period of the past indicated (neolithic, antique, medieval, steampunk etc). An additional reality-check tag, of science tag, would limit the answers to actual, historic science. That requires references. Without science tags, answers may e.g. be a mythical context, this kind of physics-past only needs to be plausible.
The physics-future tag allows for extrapolation of physics knowledge. When put with a science tag, the extrapolation should be made plausible.