Can blame Trump for a lot of things but he wasn't the only one running denial when the time to prepare was running down.
There's a few reasons for this
1) China lied about the details and numbers of the virus. As of January 2020 the WHO's official stance was that human to human spread not common or even impossible. The MSM called the flu more deadly. Talk about China in full lockdown and a lot more deaths than reported was censored on social media. Russia was even accused of spreading coronavirus misinformation in the US and Europe. Trump was called a racist for closing the border with China.
2) It took the WHO about a week after it spread to the US and Europe in big numbers to declare a pandemic while already hundreds were dying and thousands were infected in Iran, They didn't call it a pandemic until AFTER Trump stopped travel from Europe and reports came in about those infected cruise ships.
3) The guideline for social distancing wasn't enforced in most countries until AFTER Italy went in full lockdown. Europeans didn't close borders or halt air traffic until AFTER Italy went in lockdown.
4) Health experts in countries like the UK were using the wrong data models partly based on what China had reported. It showed a mortality rate of ~1% vs the 10% Italy hit soon after. When the models were adjusted to a mere 3% panic hit governments deciding to reverse their positions and moving to suppression and lockdown.