In fundamental research you don't typically know the potential applications where it will be useful. In fact I dislike the current overfocus on applicability, your research can't get media-boosted unless you somehow say it's a step in curing cancer or solving climate change. Similarly, pure math is valuable even without foreseeable uses (if pressed, they will say cryptography etc. but they shouldn't have to).
Curiosity to understand how the world works is enough as motivation in science. Applications can also provide ideas but then you can also diverge from them and follow directions that look intrinsically interesting or perplexing.
What you note is not addressing the core problem, namely that academia selects for certain non-diverse personality traits, like very high conscientious ess, wanting to please authority, tolerance of monotony etc which all lead to it becoming an inside baseball, working to scratch each other's backs.
You want to force them to turn away from their navel gazing by orienting them to concrete useful applications but what you really should incentivize is research whose main characteristic isn't that it's useful or all the current trendy hivemind consensus thinks it's what you're supposed to do, but the pursuit of understanding, the desire to see clearly and get closer to truth. And this doesn't just depend on what you incentivize with metrics but also what personalities are allowed in in the first place.