This is a huge discussion and will take too much time if we continue! What all users need understand is:
ERPNext is not designed with focus in a business segment.
ERPNext is a result of years listening the difficulties of the users, and they opnions!
If we return back to 2012, ERPNext had sorting in all columns, he had too editable grids in all forms, but the community (the users), raised the flag in favor of Mobile support. Because this, the team started a new UI, that did not please everyone, but this is the cost of all evolution of this system.
In a tecnical point of view, I fully agree with this thread, sorting columns are required, but not is required for everyone, if you need mobile, you will understand that the sorting columns dont make difference, with a poor performance in mobile.
Keep in mind that ERPNext is a incomparable product, our “brother” Odoo, on each new release get new features, new size and new latency.
ERPNext on each new release get a lot of new features, reduce your code size, in increase the performance.
We can compare ERPNext with all the others ERPs in the market, but anyone is like another, and the most important in ERPNext is the pure result of discussions managed by people like me, yours, everyone.