Your conspiracy theory wouldn't be convincing even if your facts were correct, but few of them are.
both Apple decision to source OSM and the license change happened in 2010
I've been an OpenStreetMap contributor since 2008, and the license change discussions had already been started back then. You can find evidence of the process throughout the project's documentation and mailing lists, but for an obvious example look at the revision history of the OpenStreetMap wiki page for "Open Database License" (OSM's new license) and notice that the first version is from February 2008 and already describes the characteristics that define this license today.
loosing roughly 30% of map data in the process
This is a massive exaggeration of the effects of the license change, as the actual numbers for data loss are in the low one-digit figures.
Details depend on how you count, and unfortunately some areas - particularly Australia and Poland - were hit disproportionately hard. But even though this is indeed a setback for those regions, thanks to the continuing growth the current version of the database already contains more content than we had before the deletions (go to OSMstats and switch to the yearly graph; the dent in summer 2012 is from the license change). Even though this does not mean that all the damage has already been repaired, it makes me confident that the OSM community is up to the task.
took an Open Source map (OSM) and gave gave it to himself, without an obligation to share back the updates.
This misrepresents the purpose of the Open Database License. The ODbL has an exception for produced works such as image tiles or prints, but is otherwise a share alike license. So under the ODbL Apple would indeed be able to use OSM and keep the artistic components of their products, i.e. their pretty map designs, to themselves, but updates to the underlying factual data (and derivative databases such as routing graphs) would have to be open sourced.
But the most important fact that you are missing: Apple is not actually using much, if any OpenStreetMap data under the new license! The situation is somewhat confusing, though:
- Apple have been using OSM as their primary data source for iPhoto background maps since March. This was widely published and also acknowledged by the OpenStreetMap Foundation. To everyone's astonishment, though, they decided to use a two year old dump of the OpenStreetMap database for that application ... which also means this data is not affected by the license change at all.
- Apple list OSM as one of many sources for their recently released iOS maps here. They fail to mention the license (which incidentally is an, albeit minor, violation of the requirements of both the old and new license). As a result, it is hard to tell whether they have used post-license change data this time.
- Even though some traces of OSM data in iOS maps have been spotted, this is only the case in a few remote areas (Islamabad is one of the more convincing examples). Early assumptions that OSM data might be responsible for some prominent errors e.g. in Japan have turned out to be incorrect. In fact, many of those errors would have been avoided had Apple actually used OSM data there.
So if Apple indeed set up an elaborate conspiracy to have OSM release their data under ODbL, why aren't they using it?
TL;DR: There is neither a plausible connection between Apple and the OpenStreetMap license change, nor has the event damaged OpenStreetMap even remotely to the extent suggested by the parent's factually incorrect description.