Unity stock is down about 10% since the announcement. I'm sure that's driving the action plan & messaging more than any actual feelings about harming their userbase. They knew the users would be irate, but investors... That's a different story.
I certainly sold all my Unity stock after hearing about the ToS changes. I only invested in them in the first place because I value the indie gaming community and they seemed to be reneging on that with this change.
How does buying Unity stock help indie gaming community? You bought it on the open market from somebody else who was selling it, and Unity hasn't seen a single cent of your money.
Owning stock in a company means you own a bit of that company and are participating in the journey that company is taking. The change they made to ToS made me and many others sell stock in that company, which tanked the price and probably had a lot to do with their about-face on the new policy. Buying stock in Unity wasn't about giving charity to a publicly-held company - it was about wanting to be a part of their mission (until I didn't).
He didn’t say it helped. Just that he did it because he values the community. It’s possible he is an ethical investor, where you only make investments in companies that follow your beliefs regardless of their potential profitability
Rising stock price helps a public corporation directly because corporations own their own stock, too. A high price allows a company to sell some of those shares, or issue new shares. Among other things.
Unity stock declined 25% in the first two weeks of August, and it went up 15% in the first two weeks of September. Looking at Unity's stock chart for the past year[1], a 10% decline looks pretty routine, so I think it's hard to pin this on the announcement.
Which would be surprising, I think most investors just buy whatever they're told from the board but usually don't care about customers and their reactions