Simply telling a group that, sure this guy is cool with the elimination of your people and is willing to help, but the other guy is a threat to our system… well it’s pretty rich to expect that group to suck it up.

The other guy would probably be offering to put our troops on the ground to help Israel genocide faster. It's not just that he's a threat to our system, and he is, but that he's a horrible, horrible, terrible, un-redeemable, festering piece of excrement who you can be assured is going to do the absolute worst possible thing in every situation he finds himself in, and revel in it.

Trump would gladly support turning Gaza into a parking lot, and quite likely would have US troops engaged in a war with Iran right now. So, the actual choice is Biden, who's attempting but largely failing to restrain Israeli military actions, and Trump, who would actively support them and undoubtedly support subsequent Jewish settlement of Gaza once the Palestinian "problem" has been solved.

It's an unfortunate choice, sure, but it's not a hard one.

The downvotes are because “both sides are the same” is an extremely common talking point by right wing trolls/astroturfers.

Conservatives recognized a long time ago that republicans will vote. They aren’t worried about disenfranchising conservative voters. Because conservatives will be willing to jump through hoops to keep voting. Voter ID laws, for instance, largely don’t affect conservative votes. If there’s one thing conservatives are really really good at, it’s presenting a unified front for their voters.

So when barriers to voting are put in place, they’re almost universally intended to disenfranchise liberal voters. This is true for both hard barriers - Codified legislation like voter ID laws - and also for soft barriers like a lack of time or motivation to vote. There is often a lot of liberal pushback against hard barriers, (because liberal lawmakers and activists recognize that it will unfairly disenfranchise liberal voters) so lots of time and effort has shifted towards making those soft barriers larger. This includes everything from “your vote doesn’t matter, so why bother” messaging, to “both sides are the same, so why bother” messaging.

Basically, the conservatives are going to vote conservative regardless. But the liberals might not vote liberal, or might not vote at all. So the “both sides” messaging has been leveraged by conservatives to dissuade liberal voters. The downvotes are a sort of over correction from liberals who have recognized this trend. Because sure, it could be someone who is genuinely disgusted by Biden’s actions and doesn’t feel right voting for him. But it could also very easily be a right wing troll. So many liberals have simply begun downvoting any kind of “both sides” messaging, because the default assumption is that the argument isn’t being made in good faith.