here and now vs nowadays

here and now and nowadays both are nouns.

Word	Noun	Adjective	Verb	Adverb
here and now	Yes	No	No	No
nowadays	Yes	No	No	Yes

As nouns, nowadays is a hypernym of here and now; that is, nowadays is a word with a broader meaning than here and now:

here and now: at this time
nowadays: the period of time that is happening now; any continuous stretch of time including the moment of speech

Other hypernyms of here and now include present.

here and now (noun)	nowadays (noun)
at this time	the period of time that is happening now; any continuous stretch of time including the moment of speech

here and now (adverb)	nowadays (adverb)
	in these times