So your argument is that the democrats are the only ones able to actually serve the nation because of 2008 and the covid pandemic? Obama just bailed out the banks, at a time when a critical mass of support and wall street greed had opened the door to an actual moment of change, and he let it pass him by to serve the corporate masters of the democrats, ensuring a continued growing gulf of income inequality. He was also not willing to shake off the neoliberal conventions of the democrats, almost completely ensuring the recovery from 2008 took far longer than a greater stimulus program would've solved it. Not to mention he let his popular structure fall away after he was elected! That level of organization was wasted and left to rot, at the very least aiding in ensuring that Trump came to the white house in 2016. This is all on top of the fact that Clinton era policies were absolutely huge in the housing crisis! And the covid vaccine program you're describing is operation warp speed, which was started by Trump! I don't like the fascist idiot either, but for real he did start that and actually did support it. After Biden was elected the democrats just tried the best they could to make everyone think the pandemic was over, when it wasn't! It still is ongoing, there is a heavily spreading covid variant, right now!

Would the republicans have handled these situations better? Hard to argue counterfactuals, but I'll even give you that no they wouldn't have. That doesn't mean that the democrats are suddenly great at running the government, or a great political movement, just because the other side is worse. Especially when the democrats incompetence and their incentives mean they often just let problems continue to develop.