you may not like some of this, from the OED :)

copy-writer, a writer of copy for the press; spec. a writer of advertising copy; so copy-writing vbl. n.

1911 T. RUSSELL Advertising & Publicity ix. 96 An advertiser can..employ what are known as *copy~writers.. professional writers of advertisements. 1935 Archit. Rev. LXXVII. 129/2 They have paid copy-writers and poster-designers to ‘put them across’ in nation-wide publicity drives. 1958 Times Lit. Suppl. 15 Aug. p. xxiii/1 They are to the gentleman publisher what ideas men, public relations experts, copy-writers, and designers are to the common industrialist.
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1923 H. CRANE Let. 18 Feb. (1965) 126 Truly, you must look for some editorial post, *copywriting job, or something that will relieve you of such strains. 1958 Times Lit. Suppl. 26 Dec. 748/5 Perhaps not surprisingly, copywriting (or ‘wordsmithing’, as one executive dubbed it) is the least important department of the business.

obviously this predates web use.