Phrase Counting Method

Hint: To simplify, we are now using single word descriptors. The following is deprecated.

The simplest method of obtaining a complete BOM, line by line, is to export parts spreadsheet in a FreeCAD document, and simply count them. You can count phrases by using an online phrase counter - [1]. That is your BOM Generator MVP1.0.
For this to work, the part names must be structured in an understandable way, such as "8 mm Screw #" such that every time it is copied, it appears as: "8 mm Screw #0"
Limitation is that you just need to treat parts as primitive parts, meaning descibe a material exactly such as 2x6x8, or 2x6x16. You can't do something like 'sill plate 2x6x8' - because it will not count it with 'wall module 2x6x8
Check out what happens when you copy a part, if its name allows for easy counting by examinging part name:

The count appears readily by observing the last number.
Out of the box - you can even include a BOM link to that part with URL or shortcut, so that the exported BOM can include links out of the box:

The above looks trivial - but if done - one has automated capacity to generate full and correct clickable BOMs in FreeCAD. For example, if a design contains a house design made of multiples of various modules - all the parts can be summed automatically - with ordering links provided. This is powerful help for automated custom design.
FreeCAD allows CSV export of part spreadsheets - so further processing into finished BOMs can happen readily.

Summary of Parn Naming Convention for Phrase Counter Method

Use a 2 word naming convention for parts. Follow them by a counter number such as 001. FreeCAD automatically adds part counter numbers to part names.
For transparency, use the simplest, sufficient naming convention, and always use 2 different words so that the counter doesn't count '2x8 lumber 001' and '2x6 lumber 001' as 2 of 'lumber 001'

Do not use additional descriptors for the basic part, such as 'floor 2x6 lumber' and 'wall 2x6 lumber'. The phrase counter counts both 'floor 2x6' and '2x6 lumber' without producing transparent results.
FreeCAD adds numbers after parts if there is more than 1 of that part - which is fine. '2x6 lumber 001' and '2x6 lumber 002' is counted properly as two instances of 2x6 lumber.
Make sure you have the counter such as 001 and 002 in the last point