Free Software doesn't have to compete on marketshare. It may well benefit
in terms of mindshare by favouring advanced users. Taking as an example Linux, with still single-digit usershare among operating systems, there is
sufficient user-share
among potential contributors to support the several thousand kernal contributors, as well as contributions to a wide range of system, userland, and GUI tools.
Given the focus drift that's accumulated from even modest popularity among some Linux distros, and meant not as a critical note, just a set of observations over my own several decades' experience, more technical Linux and BSD variants tend toward more technical users, whilst the more user-friendly distros (Mandrake, back in the day, Ubuntu, Mint, Cinnamon, etc.) tend to show a greater aversion to CLI and system tools, in favour of GUIs and the like.
Because commercial software does see massive network effects and attraction to mass markets, it tends to fall far lower on the user-capability curve.
This can also hit mass-market free software, with Chromium and Android (dismissing status as truly Free Software / Open Source) being cases that readily come to mind. The mechanism here is that these are aimed at advertising-promotion platforms, and hence, mass markets (Android devices number in the billions). Which is to say the polar opposite of intellectually-rewarding power-user tools.
It's not that the users' skills depend on the software licence, it's that licencing determines business interests and user-focus of the software developer.