Decoding both DVD and BD are "known things". AnyDVD was not the only product doing it.
Two important parts to doing BD, though - One is having a valid key to get past the AACS, and being able to replace it when a version of AACS comes out that revokes your current key. If your key has been added to the revoked list, simply putting a disk in the drive with that version of the list essentially "bricks" the drive for reading ANY Bluray disks until you change your key.
The second is being able to implement the BD+ interpreter to fix up deliberate errors introduced into the video... And it changes periodically.
Where the companies that sell such products get their "market lock-in" is keeping up these changes. AACS is easier than BD+, from what I read, because you don't always have to change your key when a new AACS revocation list comes out, but the BD+ programming can and does change multiple times per month.