You are only half reading the news.

Yes, revisions are valid and happen. Yes, a look at historical revisions don't show any bias.

But where are you seeing that half made Trump look good?

https://www.bls.gov/web/empsit/cesnaicsrev.htm

Biden was the previous administration.

The whole of trumps first stint?

For this year's numbers there are two possible stories that come to my mind:

1. The jobs are going ~constantly downhill and any new, revised number is going to be worse than previous

2. There is a conspiracy and initially the numbers are systematically inflated and/or afterwards deflated because reasons... that are completely incomprehensible to me. I don't even understand if this conspiracy theory should be pro or against trump.