"Everything can be outlawed, including mere use of unlocked general purpose computers as a non authorized professional in, say, 20 years time."

I think that genie is well out-of-the-bottle.

Did you see the article recently about installing linux on the microcontroller on a hard disk controller board? There's no end of "consumer electronics" that have "general purpose computers" inside them. Hell, I'm helping out some people deploying christmas lights with a half-gigahertz ARM Linux board with wifi as a controller. (hardware details here: http://dev.moorescloud.com/2013/07/06/holiday-hardware-is-op... if you're curious). They've shipped over a million RaspberryPi's in the last 16 months - they're mostly still going to be useable in 20 years time, and between now and then pretty much every toy,appliance,car,tv,phone,coffeemachine,whatever is going to contain something capable of running linux...