There is room for debate about how clear or strong the expectation of compensation was, but at least we can agree it wasn't 100% on the far extreme of "here, have this for free, I'm not expecting anything at all in return", and then going back on their word afterwards.
can donations be tax deducted ... labor laws ...
Interesting points. I think one of the ideas of the Open Source Collective as a 501(c)(6) non-profit is to provide more of that kind of legal certainty (donations aren't deductible as a charitable contribution, but may be deductible as a business expense). I wonder if it works?
Yeah, it's possible social pressure has the potential to be effective, although I think it would have to be well-organized, with someone like OpenCollective (or maybe it would be better if it was an independent organization?) that monitors and publicizes which companies are "leeches" making a lot of money off of open source, and which are "good citizens", or something.
About if the first approach can work: maybe. For the companies I know it would be very difficult to donate money. First from what budget, then I am not sure if such donations can be tax deducted, then there is always the thing if you give money to a person how do you distinguish this from hiring the person (oral employment contracts are legal), so authorities might be interested if you circumvent labor laws. So this support has to come from the top of the company. I think paying for bugfixes/features might be much easier and cleaner for companies (still takes 6 month to get him as a contractor into the ERP system)
There seems to be working examples for 'pay what you like' restaurant, but there might be much bigger social pressure.