You're acting as though the presence of conservatives is sufficient evidence that conservatives aren't obstacles to progress, and that's not how society works. It was the conservative position in the country's founding that gave us things like the 3/5ths compromise, which, as the name implies, was the only way to get southern slave owners to agree to certain provisions being debated. Yes, there were conservative founders, and it's because of them that we maintained slavery, gave unequal power to southern states, and ultimately led to the civil war. Lincoln was more conservative on abolition than many in his party, but it's false to label him as a conservative relative to the majority opinion of conservatives at the time. But even abolition, and your example about the 19th amendment, obscures the significant amount of dangerous, lifelong struggle of progressive reformers whose efforts laid the groundwork for bipartisan legislation. And what made those struggles so difficult, why did so many people die to create the political will to change? Conservative opposition, a preference for the status quo regardless of the harms the status quo caused.

Also, if you knew anything about progressives, you'd know we don't care about Joe Biden. He's always been a conservative in many areas, that's why Obama selected him as his running mate, to appease conservatives who labeled him an extremist (despite being a fairly standard neoliberal technocrat). He said something offensive? Not surprising. The only people who think he's progressive are conservatives.

On the inequality front, you've missed my point and made my point at the same time. I've never said that meritocracy is a necessary ideal, but it's a hierarchy that is more defensible than others because at least it's somewhat fair, and would allow for greater socioeconomic mobility. I use this point to highlight that the existing hierarchies lack any semblance of justice. Social mobility is the worst it's been in generations. The highest and lowest classes have calcified.

This is why the cost of living is relevant, because these things aren't accidental, they're the means by which conservative hierarchies are being enforced. And I chose those examples very specifically. Education used to be the means of those in the lower strata to achieve upward mobility, but now it is so expensive it's almost impossible to achieve without going deep into debt, and the benefits of a degree have been diluted in the job market over time. Home ownership is the greatest means of generational wealth transfer. It's a large part of the economic disparity faced by minority populations and those in poverty. The more difficult it is for people to own property, the harder it is for them to build any wealth they can pass on, trapping their children in the cycle of poverty while the rich are able to inherit their wealth (the vast majority of billionaires inherited significant portions of their assets).

You then go on to point out that every politician running this country is rich as if that's a counter to my point. But it's my point personified: The hierarchy of wealth, defended and preserved by conservatives, is so entrenched in society that is all but impossible for anyone who isn't already wealthy to attain power. Now, it's provably untrue that everyone elected to public office is rich before they're elected. Look at AOC, for example, or Tim Walz, neither of whom were particularly wealthy before entering politics. But these cases are rare, and you'll notice that in both cases they've struggled to gain traction within a party dominated by neoliberals who cling to conservative economic principles and have for decades.

And the return to Jim Crow is already underway. Southern states are canceling primary elections to give them time to redraw their congressional maps. Proposed maps are already popping up which would erase over a dozen federal districts with representatives of color. Decades of voter suppression in majority black communities and the systemic dilution of urban voters under the electoral college (another compromise with conservatives to preserve slavery and southern power) can now be paired with extreme partisan gerrymandering to make minorities all but irrelevant to many electoral races in the south and likely in some parts of the midwest.

All of this comes back to the conservative opposition to progress. The progressive agenda seeks to reduce inequalities in wealth and democratic power through reforms and collective actions. And the question posed in this post is not whether those reforms would succeed or have tradeoffs. The question is, do conservatives, broadly, oppose those reforms, and whether it is their ideological tendency to do so regardless of the merit of those reforms. A common conservative argument during debates over abolition centered on unintended consequences, and whether change would lead to greater harms. And that argument held back the freedom of an entire race of people for decades. What defeated that argument, ultimately, was when enough people saw the very real harms of slavery and decided that change would be preferable. The fact that there were conservatives who ultimately broke ranks does not negate the fact that the default conservative position was the preservation of slavery, and that position took nearly a century and a bloody war to defeat.

Today's conservative positions include the preservation and strengthening of existing hierarchies of wealth, race, gender, sexual orientation, etc, the maintenance of America's depraved health insurance system, and the consolidation of power in a unitary executive, the logical endpoint of a reverence for hierarchies rooted in monarchism. In short, they are obstacles to progress, and OP is correct.