specifically regarding the schedules of projects staffed entirely by volunteers
If you have time to post snarky comments on the Internet (especially read and respond to other comments), you certainly have the time to contribute positively to a free software project. I can think of several patches for Parrot that an intelligent, motivated person could create from scratch in under an hour--and that's just one project out of thousands.
If you don't like or don't use one project or another, that's fine. That's your choice.
But if you think that your opinion as a non-contributor should have any weight to countless volunteers who've spent countless hours creating and giving away amazing amounts of software that you can use or not use in any way that you like and which you can modify and redistribute with very few restrictions, well... you're wrong.
It's so easy to join a community--so easy to contribute something--that if it's not worth someone's time to do something, it's definitely not worth the time of the people who are actually doing things to care.
I've invested four and a half years of work on Perl 6. I've taken three novels' worth of notes in design meetings. I've read countless code in Parrot. I've fixed dozens of bugs. I've given several talks. I've mentored a handful of people. I've written several weblogs and a few articles. I've invented a couple of language feature. I've implemented a few more. I've written code in at least nine different languages to make this thing go. To date I've received zero dollars for all of this work (I've never asked for any) and a couple of free meals.
Do you think you could possibly want this language to come out any more than you do? (Now imagine how much more Damian and Larry want to release Perl 6.0.)
Do you want to be taken seriously when you criticize how long a project is taking?
Create one patch. File one bug. Proofread one section of documentation. Port one module. Run the test suite once in a while and let us know if anything fails. Do something. Just one thing is enough. (If you'd like to contribute, even if you only have an afternoon and can only do one thing ever, that's great! If you don't know where to start, find me or any of us and we'll find something you can do.)