I agree 100%. Before we started our consultancy almost 26 years ago, neither my bride nor I ever included a cover letter with our resumes. Cover letters invite the job-seeker to make unforced errors. If an employer requires a writing sample, it will ask for one.
For most would-be employees, the cover letter is a loaded howitzer aimed straight at their job prospects. Unless a prospective employer requires a cover letter--and I've not seen one who does--a pithy, well-worded resume on a single page with judicious use of bolding and font sizes will open the employment door for a qualified job-seeker.
For any such individual reading this, DON'T include your references with your resume. Instead, the last line on that single page should say (fully bolded, which the formatting here doesn't allow me to do): REFERENCES Available upon request.
Then, on a separate page with a REFERENCES heading, list three or four professional references in alphabetical order. Include job title, employer, city/state, and email address of each reference. Don't include a phone number because a prospective employer might blind-side a reference with a phone call. Omitting the phone # mandates that they use the email address first. It also respects the right of each reference not to get clothes-lined with a phone call, which they weren't expecting but which has a significant impact on your likelihood of getting that job. Reference whose work days have been disrupted might not provide as good a reference as they otherwise would.