Eh, In my experience this is not a clean distinction. My work is generally described as engineering and it often involves discovering new things about the technology, with a similar level of uncertainty. (and it often needs to be a lot more rigorous than a lot of the papers I read in the same field).
Of course. It's the real world, there is no bright-line.
But broadly if you are dealing with building something in a world with constraints (time, materials, money, speed, safety) then it's more engineering. If you are studying how things work to try to build something without these constraints without then it's applied science. If you are developing new theories then that is fundamental science.
So yes, your criticism ("far more likely to sweep big practical issues under the rug because they're primarily concerned with being something working") is accurate but by design, not a weakness.
> the applied scientist is by definition not interested in changing reality, only in studying, explaining, and predicting it. The engineer, on the other hand, accepts the explanations and predictions of the applied scientist, and then acts to change reality to achieve some goal
Engineering is applying that knowledge in a effective and efficient manner.
Engineering is something that money and time can fix. There are less guarantees with science.