Neither extreme works well. A single unchanged resume sent everywhere misses keyword matches for specific roles. Rewriting a resume from scratch for every application doesn't scale. The practical middle ground is a master resume plus light, targeted edits.
Build one master resume
Include every role, accomplishment, and skill you might ever want to mention — longer than what you'd actually submit. This is your source document, not your final one.
Tailor in three places per application
For each job: (1) adjust the summary to mirror the role's language, (2) reorder or trim bullet points to surface what's most relevant, (3) check keyword coverage against the job description and add any honest, missing terms.
What not to bother changing
Formatting, section order, and unrelated past roles usually don't need to change per application. Spend your editing time on relevance, not redesigning the layout each time.