I don’t think there are less people that give back to Open Source but I think there are more Open Source users. Because Open Source has won and is now mainstream (Microsoft is now on Github ! Not because its cool if you asked me)
But those new users have not necessarily the Open Source philosophy in mind, the one of sharing, giving back, hacking. They are more consumers than makers. Thus some can behave towards Open Source maintainers as classic customers waiting for a service (they didn’t pay for)
These parameters put more and more pressure over Open Source maintainers shoulders. Sometimes they fight back with Kickstarter and ask their users to pay for a new milestone of the project. This works but it is not ideal.
An ideal system would preserve Open Source but find a way to kind of “force” the money to flow back to makers.
I use the word “force” because this is inevitable sometimes. Why billion dollars companies do not spare a microscopic percentage of their money to support Open Source critical project they rely on is beyond me.
Does an Open Source fundation exists ? Where Open Source maintainers submit their project and, depending on how critical, useful they are, received a well deserved salary to work on it.