when I explore adobe certifications for programs such as Photoshop, InDesign, and Illustrator, I find Expert level exams from 2015 on Adobe's website (Supposedly they are updating them to 2020 sometime this year), and I've found testing for Adobe products through a service called Certiport. Can anyone tell me whether one or the other would be more beneficial for a resume, as well as gained knowledge for each program?
Certification exams, be they for Adobe Certified Associate (ACA) or Adobe Certified Expert (ACE) exams don't measure your talent or skills as a content creator. The merely demonstrate that you can pass a test on a particular software version. And nobody uses 2015 anymore because it's 5 years out of date and not available from Creative Cloud desktop app.
If you must take the AC exam to fulfill a graduation requirement or be considered for a teaching position at an Adobe Certified Training center, that's one thing. But otherwise, it's meaningless. If you want to impress prospective employers, show them a degree and Portfolio of your best work.
[Moved question from Community Help to The Lounge.]
Shame on you for speaking so carelessly as to call a certification meaningless. There are numerous benefits to a certification: it speaks to your proficiency in a particular piece of software, it communicates you are keeping current with your field if you can prove you took the test in recent years (ACA certs expire after 3), it also helps to increase your confidence, as they give you a more rounded and balanced picture of what the software is capable of. Any company that doesn't find that a useful quality in a designer is probably focusing on the wrong things.
The new exams are now available, but the program has changed a bit:
Two new ACI exams were launched in June, 2020 – one for CC Design & Layout Solutions and one for CC Video Editing Solutions. These exams will test for a user's expertise across the entire Creative Cloud workflow for each of these design disciplines. These exams will cover complementary applications and services, not just one product.
Here is the exam bulletin for the InDesign/Photoshop/Illustrator test: https://spark.adobe.com/page/8Ccmgtv8R0ebT/ and yes, there are being managed by Certiport now.
I can tell you from experience that you will gain knowledge by preparing for the exams.