When you go to the tax table after you have determined your taxable income the table is taking into account the different rates to tax the different levels of your income.
Say your taxable income is $80,000
the first 8,700 is taxed at 10%
the next chunk of income up to 35,350 is taxed at 15%
from 35,350 - 85,650 is taxed at 25%
and so on
So - it isn't that your entire 80,000 income is taxed at the highest rate of 30% because if it was the instructions would just say "find 30% of 80,000...that is your tax" (of course they probably can't count on Americans being able to find a percent). Instead they have those crazy tables that have these layered percentages built into the tables - you know they really couldn't count on us to find the various percentages and add them together.
Looks like they hope to decrease those rates on all of the income levels up to 250,000 (so everyone (even wealthy) gets those cuts) and raise the rate at above 250,000 - so only those making above 250,000 (after write-offs and deductions) will see an increase, and only on the chunk of their income that is above 250,000.