And the web has the greatest benefit of all: no proprietary-ness, no walled gardens.
Web apps typically end up storing all your data on somebody else's system, and they can limit or revoke your access at any time. I don't see how that's less proprietary than local apps.
There's a difference between data and software. Free software important. Free data is important, too, but local/remote storage is a different issue than proprietary/cross-platform software.
