Neither is extreme. TD is even held by Arminians. How can you be extreme on total depravity. Total is total. How can you be more extreme than that?
I suppose that one may have degrees of depravity that are more tolerable then others. Perhaps this is evidenced when the Lord spoke of cities that would be more tolerable in the day of judgement then others, or perhaps the depth of wickedness found in some cities compared with others.
For some, the depravity is total in the sense that there is nothing that can attain righteousness found within a person. That is meant by those who hold to total incapability.
For some, the depravity is that there is nothing good can be found, and there are verses that would hold to that thinking.
For some, there is a mixture, that is in some people, their thoughts, life, and body carry the stench of sin, while in other people they may be clean cut, well mannered, disciplined thought life, "know how to give good gifts," and yet still unbelievers.
What I mean by the extreme, is those who lump all folks into the same bag . Again, the Scriptures do speak of this type, and that all are certainly desperately wicked (from Jeremiah telling of the condition of the heart as being beyond cure).
"All have sinned and come short ..." is a statement of measurement, not a statement of the capacity to measure.
The dash between the date of life and death is horizontal. It cannot measure upwards, it is incapable. So no matter the good, the line remains horizontal.
God placed a vertical line across the horizontal not only as a cross but a plus. Believers have that necessary to measure up, not by their horizontal effort, but by God placing that which the believer lacks.
Didn't mean to be wandering in this post.