I have seen every cover letter accompanying a job application in every company I have worked for but I have never worked for a company with more than 200 employees or so.
Strange. I've worked in startups my entire career, hired over 100 developers and I can count on the fingers of one hand the number of cover letters I've seen.
Well cover letter has somewhat been replaced by an introduction email, no?
True. But there are still recommendations to email with a coverletter.pdf AND a resume.pdf. Maybe developers in Toronto don't follow those rules ...