I think that
@Dausuul gave a thoughtful response. I don't agree with all of it, but it also goes to the issue of there not being a common and accepted definition of "open license." I think that this provides a useful framework-
www.yearofopen.org
Note the most basic definition is in the first sentence-
Open Licenses are a set of conditions applied to an original work that grant permission for anyone to make use of that work as long as they follow the conditions of the license.
As I am fond of saying, the Robot Devil is in the Robot Details, and the Robot Details for this most basic definition is ... what are the conditions? That said, I would delve into further details.
For example, and this is important for this discussion,
standard boilerplate is a part of most modern open licenses. Go ahead and look at the GNU Public License (GPL) 3.0, which many people consider a sterling example of an open license.
Here it is.*
But examining the GPL... look at paras. 15-17. What are those? Oh yeah, they are disclaimers of warranty and limitations of liability! And notice that people can add material to the work under GPL and have additional permissions (para. 7).
And this is a widely adored, copyleft license that is limited in scope (it is intended for software).
Moving back to your question ... the primary issue is that OGL 1.2 is only ever going to be "open-ish," in my mind, when the following two provisions remain-
1. Any provision that the license can be terminated as to a licensee or a work without the ability to cure.
2. Any provision that the license can be voided, updated, or revoked. In other words, a severance provision should be either a traditional severance provision, a reformation provision, or both. Here is an example from the CC-
To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions. (Per my earlier discussion, this is essentially "redlining" a provision first, and then severing it from the contract second).
That said, I think the primary fault line will continue to be the moral clause; this is because WoTC desires to maintain some degree of control (at last inasmuch as they want control over how their brand is perceived) ... which is a rational desire. But retaining control is kind of against the very purpose of an open license that is disseminated in order to allow other to build upon the work you are releasing. In other words, it's almost as if they want to portray this as being similar to CC BY-SA, but retain (some) editorial control over all derivatives
and all works based on derivatives, and so on.
*If you want a contrast, you can look at the varying levels of Creative Common Licenses (
here). FWIW, CC licenses also contain some of the boilerplate, such as limitations of liability, that people are complaining about. Almost like there's a reason for it, and they have been added organically over time.