Nancy Pelosi, Chuck Schumer, Hakeem Jeffries, Kamala Harris, Andrew Cuomo, and Gavin Newsom are some of the major leaders of the democratic party.
Because the neo liberals controlled the DNC for decades, and if reps didn't vote for who the DNC wanted in those positions, the DNC would fuck with them and withhold the money that was stolen from their state via Victory Fund out of spite.
They'd fuck over any incumbent that went against them, even if that meant a republican kept the seat.
But the voting members of the DNC finally kicked the neoliberals out of power at the DNC.
The people you are talking about are still coasting off the last leadership elections in the House/Senate when the neoliberals were in charge. They won't win the next ones without the threats from the DNC.
Does it make sense now?
This is important to understand and billionaire owned media sure as shit aren't going to explain it, so if you have more questions I'll try to answer them.
Who is in a leadership position in the DNC that isn’t a neolib?
The chair, who unilaterally controls everything for the next 3 years...
If you think he's going to fight against progressives, look at the decade he ran Minnesota, it went from a purple state to deep blue and home to some of our most progressive House reps.
If Martin is a neo liberal who wants to keep progressives out of office, he's so bad at it he might as well not be trying.
Logically that means the reason he was picked is the voting members of the DNC want to listen to voters again instead of screeching at them.
Quick edit:
But it seems you're conflating House/Senate leadership with DNC leadership...
They should be separate things, but decades of neoliberalism has intertwined the two.
It's going to take another House/Senate leadership election cycle to fix that, because the last vote happened with the old DNC.