99 years to enter public domain... I don't think this is fair.
I've yet to hear any credible argument - one that doesn't reduce to entitlement and wishful thinking - for distinguishing between these asset classes.
If IP is effectively a public good held on a short lease, so is all property. If it isn't, it isn't. Any argument you can make about the benefits of putting intellectual work in the public domain, you can also make - more convincingly - about land and any other productive resource.