Isn't she currently serving?
Can't she pursue this now?
The Congress is not under the control of Harris's party, but rather is half-controlled by Trump's. That means her party and Biden could not pass anything, especially something that made her look better to voters.
Do you now mean that all of Kamala Harris' promises will depend on Congress? So, if Democrats fail to get the majority in the legislative arm, her campaign promises will not see the light of day. The truth is that eliminating taxes on tips is not on the agenda of the current government. They would have easily lobbied some Republicans who could support the bill in Congress. Harris got this idea from Trump and that's not wrong. She is free to learn from anybody as long as it will be for the benefit of the people. After all Trump cannot claim ownership of all the ideas he has been brandishing in his campaign. He has even been accused of using people's intellectual property (songs) without permission.