Bullshit. Trump told all of the suppliers to ship all of their PPE to China, in January. He even lifted restrictions on trade to China help them make the sales. Nothing to do with 0bama at all.
In 2019, Trump fired the CDC Director for "disloyalty" and replaced her with a Dr. Redfield. This nomination met with resistance as there were discussions that he was unqualified to run the agency. Sadly, most of the CDC failures can be laid right at his feet.
You say that the USA only had one type of test. ALL countries in the world only had one type of test - the WHO test.
Trump refused that one because American companies didn’t have exclusive rights to that test. So he had his loyal Dr. Redfield take care of producing a “made in America” test that American pharmaceutical companies could profit from. Redfield fuck it up so badly that they had to start over.
Months into the pandemic, the USA had no testing system. Finally Trump just said any company can sell any test they think will work. Every company sold something different, with differing ways of processing. Not all of the tests worked. Chaos.
Trump also failed to renew the service contracts on the national stockpile of ventilators.
This is simply mismanagement on a catastrophic scale.