Exactly. Parent is exaggerating. Also, highest tax bracket is 37% (2018). Yeah, I'm arguing about 1%, but that's also for individuals making over 500k, or couples making over 600k.

50k to 100k income raise bumps you up 2% in tax rate from 22% to 24% (assuming individual).

If parent was talking about raise on top of what they have, then the worse affected rate of change would be the 24% rate ($82,501 to $157,500) to 32% rate ($157,501 to $200,000).

These numbers are similar, but less affected with MFJ.