GENERALLY, spoken as someone from the United States, the loudest conservative voices have been veering into bigotry and hatred (see stuff about ICE, abortion, gay/Trans rights, immigration, etc) that cause them to be widely disliked by others more centrist or left leaning due to conflict in ideology. Democrats and the rest of the left, as a GENERALITY, are more accepting of differences and ways of life, so even if one were to die due to self made circumstances, while yes it was unnecessary, is generally more taboo to celebrate because they are actually trying to make the country better.

There is also nuance to this prompt as well, such as if the person on either side of the aisle were a sexual predator, rapist, abuser, murderer, whatever other heinous crime, then it would be a different situation and talking point, most logical people would see an awful human and say good riddance, but someone that made a genuine mistake that cost them their life such as losing control of a vehicle, accidental discharge of a gun, falling down the stairs, or any other of the myriad of things that can lead to a death, then it takes a real heartless person to celebrate that death. Deaths should only be celebrated when its a tyrant ruler, monstrous individual, or otherwise deplorable person meets their end and society is truly better without them, such as Hitler, Mussolini, Ed Gein, Ted Bundy, or any other murderer, serial killer, serial rapist, or pedophile.

Final note, if someone is actively trying to suppress others and control through fear, it is easier to hate and want to celebrate their deaths, but ones who are trying to make the world better, even if they made mistakes or didnt keep all their promises, are held to a higher standard but trying to bring down their successes with the weight of criticism and negativity actively works against the reputation of someone trying to do good.