Okay so here’s dinner context you may be unaware of. I believe it was Newt Gingrich who either came up with or standardized the core modern republican propaganda pillar: Attack attack attack, always attack, never compromise, concede only if you have literally no choice, then attack harder. That’s why the left has slid so far center; they keep trying to compromise and the right will not budge. Now the Democrats look like the Republicans back in the 80s, which is why I call them Republicrats.
Meanwhile Dems are trying to hold themselves to at least some level of standard. Add to that that Trump and his kind are authoritarian; their psychology allows for no criticism of any kind, seeing them exclusively as attacks against them. So now you have not only GOP and Trump cultists jumping on every single thing they can as hard as they can, and the self-aware Democrats calling out what they perceive as bad. The Republicans won’t do that; they never attack their own side without orders from the top, which indicates to them that the target is out of favor with the leadership.
Tldr; because the Democrats refuse to accept that the Republicans can’t be beaten by playing nice.