DVDs and Blu-rays also have stupid geographical restrictions. They come marked with region codes, and DVD players will only play discs from their home region. You have to go all the way back to VHS to be free of that particular corporate "innovation."
> Try watching a European VHS cassette in North America (or vice versa).
That's not a georestriction, but a difference in media protocols. You could easily buy a compatible VCR. Heck, in some countries, Japan marketed VCRs that supported both PAL and NTSC (I had one of those) because those countries would have a significant influx of VHSs from both Europe and America.
It's like saying the choice of 110 vs 220V (or 120 vs 240V) is a "georestriction".
This would actually be a plausible excuse for region locking. If the MPEG stream were somehow optimized for NTSC/PAL.
If course the most likely reason is corporate greed, but it's also fun to consider other possibilities. Another hypothetical reason would be for sales in Islamic nations where certain content is prohibited. They could show the government censors that there is some level enforcement to prevent "illegal media" from being easily watched. Whereas without it, the government could have potentially made DVDs illegal in their entire nation. I'm trying to see this through the lens of the design committee back in the early 90s.
This is no longer the case with 4k UHD Blu-ray. They CAN be region locked in a technical sense, but I believe that there have only been two ever released that utilized that functionality. For the most part you can just buy one without worry.
The flipside is they just price the discs so high that nobody wants to buy them in the first place. DVD boomed because they were reasonably priced, notably being cheaper than the VHS tapes they were replacing. Blu-Ray discs still tend to be priced as a "premium" product, even though the competition isn't an even more expensive physical medium but much cheaper streaming. There is really no mystery why the entire industry segment is dying. It is the same reason S-VHS and Laserdisc were flops while cheap DVDs sold in the billions.