Actually Brogan, I very strongly disagree with this.
Through the creation of the marketplace / resources area it is xenforo itself that led to the growth of the add on community. TMS is actually the 5th most downloaded add on and has been installed by well over a thousand license holders. Many add ons support TMS.
Given the relative success of TMS I think that if the responsibility lies with anyone at all, then it absolutely is the responsibility of xenForo and not that of the add on developer. It is xenforo that has decided to adopt this as native functionality and in doing so has created potential upgrade conflicts for from what I can see at least 1000 users. It is surely not the responsibility of the add on creator to create another add on which will help users remove his add on - that is thoroughly ludicrous.
Should the add on developer have the forsight to look into a crystal ball, see that his add on will become hugely popular in this case and then one day adopted natively leaving all his add on users practically up sh!t creek then add ons wouldn't get made.
Xenforo has access to the TMS code, they no doubt inspected it at some depth during the making of this feature and the very least they can do is to provide an upgrade path.
For the record, I do not run TMS but if I did I would be quite peeved.
In xenforo's defence, I have heard no official line on this at all so it may even be in the bag for another time.
