First of all, opposing a policy just because the other side proposed would be stupid.
But, more importantly, Harris specified no tax on tips for service and hospitality workers only. Trump proposed no tax on any and all tips. This means that anyone can change to a tip-based reimbursement and pay no taxes. You could get an invoice from your attorney with a line for tip.
I oppose this policy from either side. Income is income, and one group of workers should not get a tax break that others don't. If you want to give low income workers a break, raise the standard deduction.
Trump did not invent this idea, it has been around for quite a while.
I don't know the specific case or the tax laws relevant here, but on a general point it is common for opposing political parties in democracies to agree over some matters.
Jane S 