I think politicians should avoid even the appearance of impropriety. They likely hired Hunter Biden because he was the son of Biden, so I object to that. However, the story that Trump is pushing has been debunked many times. The investigation into the Ukrainian company started before Hunter joined, and it was over before Joe Biden had the prosecutor fired for being too lax.
I am not absolving the Biden of all responsibility but Trump's claims are largely unfounded. The fact that Trump's children work in the White House also without any kind of experience, and nobody is giving a damn about the emoluments clause, means they are raking in large amount of money too.