How are we supposed to utilize price tiers in the new layout if it doesn't obey the set rule and gives no option to adjust it?

I'm here to provide some insights about price rules in QuickBooks Online (QBO), @RMountsSales24.

The price rules feature is unavailable in the new invoice experience.

As a workaround, integrating a third-party app into your QBO account is another way to apply price rules to your invoices. 

You can submit feedback to improve QuickBooks and our engineers will take a look at it for future enhancements.

1. Head to the Gear icon at the top, then click Feedback.
2. Enter your comments or suggestions.
3. Then select Next to submit Feedback.

I've added this article to manage and personalize your sales form: Customize invoices, estimates, and sales receipts in QuickBooks Online.

If you have more concerns related to price rules in QBO, feel free to reply, I'm just around the corner to help. Have a good one.

That is asinine.  To go from an integrated system back to a 3rd party or manual entry for price tiering is a terrible move.  That significantly increases the time for invoice entry in addition to figuring out how to integrate the 3rd party option.  We are paying for a system that worked fine.  Your update broke it. Now please fix it. That was not an acceptable answer or workaround.