Earlier quoted context omitted.
If we assume science still has new things to tell the world, who better for researchers to share their discoveries with than the next generation? That’s the argument, anyway. In practice, it’s a crapshoot. Many researchers are dreadful educators due to incentives, training, and disposition. Every now and then you’ll run across a researcher who is also a great educator, but there’s no institutional force that pushes t…
That explains why you would want researchers to teach students, but not why students (who generally have little to no income to speak of and are already struggling with university costs in the US) should directly pay for research
I personally think undergraduate at a big (research) university is bad for most students. But the prestige ain't nothing.