You are making an assumption that Republicans only donated to Trump and not to Biden. The Bloomberg article is about donations based on profession and large employers, not political affiliation or party.
He did. He's also probably correct. I'm pretty sure R/D affiliation is a fantastic feature for tracking the end target of any specific donation. A small subset of R's might donate to Biden, but those are likely swamped by the general split across party lines.
You are making an assumption that Republicans only donated to Trump and not to Biden. The Bloomberg article is about donations based on profession and large employers, not political affiliation or party.