To make sure our apps are as reliable and accessible as possible, especially in an increasingly globalized marketplace, we need to support constrained devices—they're how most users are accessing the web globally. OMT offers a promising way to increase performance on such devices without adversely affecting users of high-end devices.

[Apart from 2 very specific cases where treatments needed to be done without the user request] I have seen exactly zero other instances where Web Workers would have improved the user experience.

How to reduce the First Input Delay? By cutting the code down, making the browser execute it during idle periods and routing the most expensive tasks to Web Workers.