As I mentioned in another comment, the problem with 2 is that employers routinely hire people who don't meet the minimum requirements. If you don't apply to those jobs because you don't satisfy that one bullet out of the 6 they listed, you're hurting your chances.
They can fix it by actually posting minimum requirements.
I believe that that still won't stop applicants who don't meet the minimum requirements from applying. What's the cost to an applicant to spam their resume to an additional listing? Almost $0. What's the possible reward? Very high, if it's less than a 1 in 10-million shot that the company will decide to hire you.
How many Powerball tickets would you take if they cost $0?
I guarantee you that if your application process requires a cover letter, and will not proceed until you upload one, you will probably lose a fraction of applicants.
You can ask them to put the string "xyzzy" in the cover letter as a screening measure. This will almost certainly curtail the bulk of applicants.
The basic idea: Add enough friction to the application process so you'll get higher quality candidates. This is trivial to do.
They can fix it by actually posting minimum requirements.