Harvest Moon nails it up above.
As a practical matter, most high schools have had to build a fairly extensive rec letter producing machine. Since every senior needs one or two teacher rec letters, and often a counselor rec letter as well. Plus extra rec letters for some college specific requirements. Plus even more letters to apply for various scholarships, internships, programs and jobs.
At my kid’s HS, that system involves the submission of a student resume, plus a parent generated brag sheet. Plus an extensive assigning/matching process so that the rec letter writing burden is spread out evenly among all the various teachers. A kid can’t just ask their favorite teacher to do a letter. All of this then has to be tracked online in order to make sure that hundreds of letters get to hundreds of destinations in compliance with hundreds of deadlines. All in all, it is a fairly industrialized, high volume, sausage making process.
The teachers and counselors at my kid’s HS are highly experienced rec letter producing bots. They don’t ask for first drafts because they don’t need them. They have previous hundreds of prior precedent rec letters that they use and reuse and reuse. Male soccer player who wants to study STEM at Harvard? They have a form for that. Female theater kid for UCLA and psychology? They have that form too.
Marv’s views reflect an ideal, low volume context that probably applies where a small number of college kids are getting a small number of rec letters (perhaps for grad school program applications). At the HS level, such a quaint system would never meet the volume and time demands.