^ Just a reminder that domestic violence calls about reproductive coercion doubled after Roe was overturned, in case you're noticing a pattern.

Horseshoe theory is definitely a thing in that the extreme left is every bit as hateful, intolerant, and authoritarian as the extreme right, they just direct it at different groups.

The more militant members of the far left for example are very open about calling for murder, rape, and torture of those who disagree with their opinions about gender, are openly racist towards white and Asian people, (who they label as "white adjacent") openly sexist towards men, openly ageist towards older people, and try to destroy the lives of pretty much anybody who doesn't conform to their beliefs, to the point of trying to get people fired from their jobs or harassing and doxing people for expressing non-left views.

Thankfully, the extreme left currently holds comparatively few positions of official power, in the US anyway, but I'd argue they're just as toxic as their counterparts on the far right and if they had their way we'd be living in a totalitarian dystopia.

Ehhhhh... While I don't disagree that there are people on the left who express these positions, I think saying "the far left are very open about calling for murder, etc" kind of implies the opinions of a group of radicals (I'll leave out personal judgements on the size of that group) are inherent to far left ideology. 

Some on the far-left support violence. Some don't. Some on the far-right support violence. Some don't. Some in the center support violence. Some don't. If American politics as a whole were to move to the far-left, there would be ample opportunity to do so in a way which does not amplify the voices of those who support this violence. There is a lot of space on the far-left that is inherently and vehemently opposed to violence, including that which is widely accepted in our society (such as our policing system or the death penalty). It would not be inconsistent with leftism to be non-violent...

Yeah that is a fair point.

I probably should have been more clear in that I am referring to the extremists, not "everyone on the far left is like this."

I don’t think what you are describing is horseshoe theory though, basically what you’re saying is that violence & intolerance can exist regardless of where you land on the political spectrum.

It's more that the further you go towards the extremes of both left and right, the more you encounter a lot the same behaviours; bullying, moral absolutism, a hatred of certain groups of people based on sex/gender/ethnicity/etc, a belief that the ends justifies the means and that everyone else must be forced to conform to their ideology, heavy restrictions on what people are allowed to do and say, intolerance of any difference of belief, the use of coercion, ostracization and censorship to silence and punish critics, etc.

That's not to say that the left and right are equivalent of course, that's not what I mean at all, more that extremists of both stripes exhibit a strikingly similar playbook.

Hm, the most common "far-left" I see are those who take the stances of defending authoritarian regimes because they dislike America, they'd be those on the left who will take a bullet for people like Putin, defend Russia's invasion of Ukraine, all because America sees Russia as their enemy and vice versa, it basically comes down to "America bad so their enemies must be good" and that's the extent of their logic. Maybe I see those people far more than the descriptor above though because I'm heavily invested in the Russia/Ukraine war.

Still, I would say they are overall less bad than those on the far right, simply because the far right also share the same stance when it comes to Russia but they also want to take down everyone different from them too in their own countries, they will go after anyone who isn't a straight white male, so on a balance of numbers, the far right affect more people than the far left and the far right don't defend Russia only because they think America is bad, they defend Russia because they see that authoritarian regime as a utopia that America should follow.

What you are describing is human behavior. The more passionate/obsessive someone gets, the more likely they are resort to any means necessary and push out others who don’t feel the same. That not horseshoe theory, that’s being in a bubble and thinking you are superior.

Horseshoe theory says the further left/right you go, the more you have in common with the other side and less in common with the center. When discussing policy issues, horseshoe theory is bullshit. Let’s look at a few examples.

Healthcare-The left wants socialized healthcare. The right wants private healthcare.

Abortion-The left wants abortion to be the decision of a woman and their doctor. The right wants to ban all abortions.

Climate Change-The left wants to transition to renewable energy. The right wants to expand use of fossil fuels.

At what point do people go so far left/right that they start seeing eye to eye on these topics and others?

Indeed, the far-left is greatly outnumbered by the far-right. I'd say by a factor of at least 10 in pretty much any democratic country. The far-left is commonly so small that it isn't politically relevant, meaning as a political party it either fails to clear the threshold to get into the parliament or it gets just barely in.