It's not bike shedding, it's a valid concern: either I type it infrequently enough that I will probably forget, meaning I'll have to either remember after I type it incorrectly the first time or look on Google, or I type it frequently enough that it actually does affect my productivity. In my eyes, having no default and forcing users to type in something like -r requirements.txt or -p is just forcing users to do something that can be sensibly defaulted and wasting their time. It's like in an elevator, are you expected to close the door by pressing the close door button every time, or open the door when you arrive to the floor? No, because the elevator manufacturer knows getting in an elevator and pressing a floor button means you want the door to close and open for you. The same can be said about pip install: if a requirements file (requirements.txt, Pipfile) exists, and the user types in pip install, it's simple enough to infer that the user wants to install based on the installation file parameters. What's wrong with that inference? Dogma?
An elevator door must always be closed prior to going up or down in a building.
Pip will sometimes install from Pipfile, sometimes from requirements, sometimes from another command line argument. What if both Pipfile & requirements.txt exist?
Requiring a user to say what they want from a command line tool (that takes barely two seconds to type) is hardly an exhausting task.
