The Republicans are using the budget reconciliation process to pass this bill. This means that when it goes to the Senate, there is a 20-hour time limit for debate, and it can be passed with a simple majority, thus removing the Democrats' ability to filibuster. As the Republicans control both the House and the Senate, albeit narrowly, this keeps the ball in their court regarding the finer details of the bill.
Tax cuts and economic growth
The extension of prior tax cuts doesn’t provide a stimulus for growth or worsen the annual budget deficit. Growth is about change and to elicit a change in the growth rate you would need to see a change in the tax rate. The change in tax rates occurred in 2017, so the positive impact on growth has already been experienced. Not extending these tax breaks that are due to expire would be a negative impulse for economic growth but extending them won't push the US growth rate higher on its own.
Impact of cutting tax on tips
Cutting tax on tips and overtime could affect tax receipts, contracted hours worked, and inflation rates. Of course, the first impact is that tax receipts from them fall to zero. Differing tax treatment might also encourage more hours to be billed as overtime rather than as regular contracted hours, negatively impacting income tax receipts further. Additionally, it could lead to a reduction in hourly pay but more tipping., This could put downward pressure on officially measured inflation rates but not on real world costs for consumers.