> How’s the ink jet printer industry doing these days?
There's good competition from cheap laser printers.
> If everyone does it the only fix is a law.
What makes you think so? You could first try opening up the market more. You can lower barriers to market entry. Eg for new upstarts, for established companies in other industries trying to branch out, and for foreign would-be rivals, too.
HDMI includes multiple protocols: https://news.ycombinator.com/item?id=31828193
HDMI blocked recent AMD contribution: https://news.ycombinator.com/item?id=39543291
Ink jet printing is protected by patents. They will expire eventually.