Where exiftool wins
Coverage, precision and scale. It reads formats this page has never heard of, writes individual tags, and processes ten thousand files in a loop. If you work with files professionally, install it. Nothing here replaces it.
Where this is more useful
When you have one file and a question. When you are on a phone. When you are showing someone else why this matters and a command line would end the conversation. When you are on a machine where you cannot install software.
Same principle, different surface
Both do the work locally. Neither sends your file anywhere. The difference is that one expects you to know what to ask for, and the other shows you everything it found and explains why it matters.
The command lines worth knowing
To see everything in a file: exiftool yourfile.jpg. To strip all metadata: exiftool -all= yourfile.jpg. For documents, mat2 is the equivalent and handles office formats well.