For the load-bearing terms, yes: skill names, certifications, and job titles should match the spelling in the posting, because recruiters search the ATS database by those exact words. For everything else, write like yourself. Vocabulary should match; sentences should not.
Search does not reward creativity. If the posting names a certification with its official abbreviation and your resume spells it a different way, a query for the version in the posting can miss you. The safest move for any term you cannot predict is using both forms once.
Keep the matching surgical. Change the handful of searchable nouns to the versions the posting uses and leave your accomplishments in your own voice, because after retrieval a human reads the page, and pages assembled from the phrasing of a job ad read like nobody in particular.
“Match the nouns they search for, keep the sentences that sound like you, that is the entire trick.”
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