Honestly until actually looking at it earlier this year I assumed the Lite version was just a somewhat pared down version but people should really look at the screenshots[1]. It's painfully mocking of the change with an intentionally kids-drawing-like UI and seemingly zero configurable settings outside of three sliders.
Edit: typos
Adguard is working on an actual replacement of their Ad-Blocker that comes as close as possible to the V2-version:
https://chromewebstore.google.com/detail/adguard-adblocker-m...
I can understand his frustration. uBO will lose what makes it special, the ability to serve as a wide-spectrum content blocker. He wants to make a statement.
And those features make uBlock Origin much more effective. With Lite, filter lists can only update when the extension does (delaying new filters which stalky advertisers will use to their advantage as they can update faster than the extension), some filter types not supported, no element picker and other options for crafting your own filters, no external filter list support, …