It really isn't about enforcing it. How do you enforce that is the question that even GPL struggles with.
It's a simple value proposition and a simple premise. If you're commercial, we're commercial. If you're not making money, you can still have it.
Compare that to just someone buying something. Individuals and especially businesses will buy what they need to buy. Imagine someone insisting "you don't have to buy me, but I am hungry". That's not even a business model. I find it's the value proposition is what is broken with most OSS. It's virtue signalling plus relying on donations. NPR does that, except they spend hours on the air begging for money. OSS might work if they were given the airtime too, but usually all the time they have is a few sentences the "shopper" reads before they hit the (free) download button (or enter the git command or whatever).
Just adding to this for the record since this was silently downvoted.
Most businesses make decisions based on $$. And they are happy to buy anything that helps their business. It's the cost of doing business. Think shopify apps. Most of those apps could be open source even if the only way to install them instantly was buying them through the app site. So having a paid for app for an open source project would be a great way get paid (or fund raise). Kind of like Linux being packaged for sale on the shelves of bookstores. That wasn't free, but people would buy it.
For business transactions, adding virtues and missions and meaning doesn't really come into play unless the marketing department has some plans that coincide with whatever virtues being sold. If the business is small, then maybe the founder. But again, it's not directly relevant to the product and use of it. Activism can be distracting when all you want to do is take care of business.
"If you agree with me, help me (or don't, you can still have it)" is a tougher sell compared to "this is $100, thank you, btw i believe in this" especially to the person/entity that could easily afford it (and pays for proprietary licenses already).
It's clear that if more OSS projects did better at making themselves money, they'd survive and maybe afford the price of continuing to improve and get better. This is in the interest of open source. I never took os to mean non-profit, although it has been synonymous with not-able-to-profit for quite some time now.
If OSI is an authority, maybe it would be in the best interest of "the community" if more help (in the form of guidelines and best practices) was provided in recouping development costs.
We have lots of people running around with "open source" projects worried about licenses when in reality they it provides them little if any protection against anything. This is owner of "open source" projects with dead community and fewer users worried about being exploited by "commercial" corporations and thus has foolishly believes that they can entrap "commercial user" with fancy IF/THEN/ELSE, statement in GUI license prompt. If tomorrow AT&T stiffs my bill with an extra $500 I and they refused to reverse the charges, I would probably eat those fees rather then waste more time and effort with money taking AT&T to court to get a judgment against them.
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.
It's a simple value proposition and a simple premise. If you're commercial, we're commercial. If you're not making money, you can still have it.
Compare that to just someone buying something. Individuals and especially businesses will buy what they need to buy. Imagine someone insisting "you don't have to buy me, but I am hungry". That's not even a business model. I find it's the value proposition is what is broken with most OSS. It's virtue signalling plus relying on donations. NPR does that, except they spend hours on the air begging for money. OSS might work if they were given the airtime too, but usually all the time they have is a few sentences the "shopper" reads before they hit the (free) download button (or enter the git command or whatever).