It is part of the general tendency toward greater simplicity of expression which has developed the clear and simple English of the best contemporary writers out of the involved and ornate style of the period of Queen Elizabeth.

An ornate and involved style needs a good deal of punctuation to make it intelligible, while a simple and direct style needs but very little help.
This progressive change in the need for punctuation and in the attitude of writers toward it accounts for the difference in usage and for the difficulty in fixing rules to cover all cases.

The present attitude toward punctuation, especially the use of the comma, is one of aversion.
The writer is always held to justification of the presence of a comma rather than of its absence.

Nevertheless it is quite possible to go too far in the omission of commas in ordinary writing.

It is quite possible to construct sentences in such a way as to avoid their use.