I am a lawyer, and yes much of it is copyright violations, and breach of the electronic license.
Sorry, but having made my living in areas that often intersect with various parts of IP law, and having been a long-time friend of a man with a vast amount of experience in this area (who does happen to be an attorney) I find your legal reasoning simplistic and inaccurate. You may well be correct in advising people to stay clear of this kind of issue, as many of the things discussed here fall into very murky legal water, but nothing discussed here is clearly and inarguably either a breach of the DDI EULA, the GSL (4e is not licensed by WotC under the OGL), etc.
The OGL specifically excludes electronic tools and games. Nobody can use any WOTC copyrighted materials with those things, without their permission.
As pointed out above the OGL doesn't govern 4e, the GSL is a license under which you MAY use some WotC 4e content, but if you haven't signed a GSL license agreement it is irrelevant to you. I doubt most users have. Note that DDI is not governed by the GSL either, though if you have signed one it might have some impact on what you can or cannot do.
You can likely use your old character builder with the old set of data that doesn't include most of the books and any of the errata. But that's not what people were suggesting. They were suggesting using it with new sets of data - which is copyright violation.
Please explain EXACTLY why you would say this? Nobody has ever clarified the issue of format shifting. I have access to data in the DDI Compendium, if I reformat that data for my own personal use, even if I store extra copies of this data, there's no general legal principle under which this is a copyright violation. You should know this. In fact this must be true, as I clearly have the right to extract data from CB in order to form a character sheet and use it.
Nobody is allowed to distribute that data or receive a distribution of that data other than through WOTC, and only as a subscriber, and only under the terms and use they permit (which is currently with their current online method of accessing it).
Again, this is not clearly entirely true for several reasons. Just the idea that people 'cannot distribute data' is a highly dubious statement under any legal theory. Facts cannot be copyrighted.
All of this was in the license agreement you had to agree to, in order to subscribe in the first place.
Have you read that agreement? You might want to...
I don't think there is anything "deeply controversial" about any of this. It's all pretty cut and dried copyright and license stuff. Legally, you can't do it without breaching copyright and/or the license itself. There's no gray area to it. You're either breaching a license you agreed to, or you're using copyrighted material without a license to do so. None of it is in the public domain, none of it is OK under a prior OGL, none of it is OK "because you paid for access at one time".
Now...will WOTC come after you? I personally doubt it. But, that opinion is given freely, and you get what you pay for.
You're welcome to your opinion of course, but you would be wrong about the clarity of the law or lack of controversy. In an day and age when things like Aereo provoke appeals to the Supreme Court over subtle nuances of legal interpretation it is just patently ridiculous to believe that anything is clear about these situations. Its not even close to clear whether or not you can make a copy of a song off a CD you own, reformat it into MP3, put it on a thumb drive, and play it in your car on the way to work. Its not even remotely close to clear what the legal status of CBLoader would be. I'd lay better than even odds on WotC losing that fight if it were every hypothetically brought to court. It would certainly be a VERY complex case with a number of different aspects.