I'd like to think that Bernie winning the primaries would've actually energised the left wing of the US. Most of the apathy not just in the US, but all over the (western) world stems from the fact that the right always has a charismatic populist mouthpiece while the left keeps bringing out all the old, broken records, pushing actual trailblazers to the back.
With what support Bernie had, he could've easily moved tons more voters than Hillary could've ever dreamt of. Not just in the presidential election but all the other House and Senate and governor and state senate and mayoral votes.
But let's presume that didn't happen and Bernie is now POTUS with the same level of support as Biden had in 2020-2024, and with the same congressional setup as you guys ended up with in 2016.
The reason why Biden's milquetoast agenda didn't go anywhere was because he already did 50-60% of what the conservatives wanted, and readily negotiated the remaining 40-50% down to 10% just to get things passed. Of course that would barely move things anywhere.
Now think, if Bernie came out with an absurdly social-democrat plan/bill. 100% opposite of what Rs want. Even if THAT gets negotiated down to 10% to get past... that's still a thousand times more progress for left agenda than Biden could've ever hoped to achieve.
Trailer Grease has none of the pull the orange turd has, though. Most of MAGA considers her nuttier than squirrel shit and would NOT vote for her.