I have a couple digital certificates from Coursera, putting them on my resume definitely gave me leverage in applying for jobs where my actual degree was not a 100% match. In a way, once you are advanced enough into your career and an additional degree does not make much sense as an investment, a great way to go is to get certified online in some areas. Similar to any extra credits I could've taken in uni, but with higher value now actually as I choose the courses that complement my already existing job experience and even help negotiate better pay as well.

YES! I took @davechesson 's course about Amazon ads. For a while a posted this on my website (I got 100%!) because I also help people publish books and market them (Amazon ads etc.) This helped boost my authority.

I have received digital certificates from many fields, most notably in the field of Seo and Digital Marketing. I show it on my linkedin and my cv. I usually prefer the free ones.