I don't think they are under-estimating, or even close. It's like taking a solid b student and grading them next to the kid eating paint chips and torturing small animals and pretending it's the same. Even in modern times, look at economic accomplishments of this admin, legislative accomplishments, etc. Fighting for things like a higher min wage (though it failed.)
Stop blaming people for not voting for them.
Fuck no. Every time in my life we've voted in Republicans it's led to one catastrophe or another. Sure you can make an argument that Dems need to be pushed to the left, but the choices are between:
a) the party who isn't improving your life fast enough
b) the party these days that are literal fascists responsible for multiple financial collapses at this point, millions dead from wars they start, failure to manage a pandemic, extreme wealth concentration, that is looking at our planet on fire and still doesn't meaningfully acknowledge that our policy is causing it. Book bans, loss of bodily autonomy for half of the country, destroying education, ensuring discrimination in law, bringing back child labor.
If you're voting republican in 2023 or not voting democrat, you're a sociopath, billionaire (whoops said the same thing twice), or a fucking moron*. There is no path to a more progressive country that comes through allowing fascists to burn it all down.
I suppose I could more charitably say "extremely, profoundly ignorant in a way that almost has to be a choice at this point."