The thing being disputed isn’t timing etc. it’s the concept of being “pushed into” a tax bracket. In the US at the federal tax level your income is taxed in buckets.

If the brackets are 10,000 @5%; 100,000 @10%, if you make 100,000 your first 10,000 is taxed at 5% and the next 90,000 is taxed at 10%.

Outside of long/short term gains, all things being equal, the timing is not especially important