Learn English – Comma after ‘I think’, ‘I hope’

The comma is used for setting off nonessential explanations. If an explanation or definition occurs as an appositive it should be set off with commas:

When the nonessential explanation is not at the end of the sentence, like in your example, it should be set off with a pair of commas.

If the nonessential explanation is placed at the end of the sentence then only one comma is needed.

Punctuation is a matter of orthographic convention. The primary purpose of punctuation is to reflect the clausal structure of a sentence. The secondary purpose is to identify phrase boundaries where the absence of such markings could result in loss of clarity.

There is no grammatical requirement to separate clauses or phrases using punctuation marks, and a sentence does not become ungrammatical when no punctuation marks demarcate its clauses and phrases.

In the worst case a sentence if it is complex in its structure becomes unclear to the reader when it lacks punctuation.

In your example sentence you can use a comma or omit a comma after nowadays.