Why always start with cat? Not using cat when you don’t need to means less typing, more efficient and mor robust code. Why use it if you don’t need to?
cat file.txt | somemonstrousoneliner
immediately tells me it's reading file.txt and doing something with the contents.
Burying the filename deeper in the string makes it harder to figure that out.
It's a good thing to be aware of the differences when needed, but often the execution speed is not the reason for writing a bash script.