At my old company I offered to help with the hiring. I said we should make job postings and just see if a great candidate applies.
My CEO told me "oh, we already have some postings. Let me give you the credentials".
I log in to (BreezyHR). There's over 2,000 applicants in the last 6 months. Tailored resumes, cover letters, everything. All the effort people put in to applying. Never even acknowledged by someone at the company. Reading the cover letters from people saying it would be such a great fit was kind of sad.
I've stopped tailoring resumes and doing cover letters. As someone who has been on the hiring end, they make maybe a small difference but the amount of time spent isn't worth the potential upside.
Keep in mind that the people doing the hiring don't want to be reading resumes either. That's why networking is still the best way to land a new job.
If I were applying I might do a cover letter for like my top 2-3 picks just to try and tip the scales.
I do the hiring for my department and most cover letters are AI/template garbage but sometimes I'll get a short and sweet one that seems genuine and it gives a legitimate edge.
Oh, and also, all the information in your CV that you also painstakingly rewrote into our forms, is going to be spread around to other companies who will use it to send you spam and phishing messages.
Good luck with your future endeavours of staying sane with others trying to get money out of you, that you don't have.