If you don't enforce your license, what's the point of having it? Lawyers aren't cheap, and international law is incredibly complex.
How do you expect to make money if no one pays you for the commercial license because you don't enforce it?
How do you expect to make money if no one pays you for the commercial license because you don't enforce it?
Many of these "open source" projects don't need licensing because no one is using because they don't have anyone to license too. You can't pay a commercial user to use this code even if you wanted to. These projects are akin to the people that start side businesses but spend all the time and money registering for an LLC and SEO advertising but have no work or customers for their side business but appear busy day and night working on their hustle and reports losses on their income tax and pay the accountant extra to setup tax shelters for imaginary income that aren't coming but that's what they saw someone else do and thus they need this and that tax service as well.
One could arguing enforcing open source is harder to afford specifically because you aren't making money off of it.