As someone who also spent six years in grad school, I’m entitled to say grad students are generally remarkably unproductive. Much of their ‘research’ work after the 2-3 years of classes is best considered continuing education. Most of them suck as TAs too. They don’t need to make a living either - They just need to get by for 5 years by living with roommates and eating ramen. It’s what I did.

(And it’s not true grad students ‘often’ write their own successful grants. The vast majority of STEM grad students are supported on stipends from their advisor’s research grants or do a TA-ship when desperate.)