Those systems may not have had an eShop, but in the days before it, I suspect not having region locking was as helpful there too.
Those systems may not have had an eShop, but in the days before it, I suspect not having region locking was as helpful there too.
Additionally, when Phoenix Wright first got localized for the DS, the print run was very small. Someone realized that the English script was already embedded into the Japanese version of the game--you simply had to go to the language options and toggle a button to switch it to English. This made importing a popular option for people who couldn't find--or didn't want to wait--for the Stateside version. I remember vividly discussing with my brothers whether we wanted to "risk" waiting for the US edition and not being able to find one, or importing and having to deal with toggling the language at every startup.
Which might explain why most handhelds were never region locked.
It's about price differentiation between different regions.
That all said, some NTSC games were still released for European markets without changing their timings. Sonic is one example of this - it runs slower, the music plays slower etc. For that reason I usually play Sonic on NTSC console rather than the PAL one (yeah, I have a whole room full of old computers and games consoles. It's sad but I love it).
I thought the DVD region locking had to do with the old school movie distribution rights systems that were in place. i.e. Fox would sell the rights to their movies to multiple companies in different regions for redistribution outside of North America. Allowing a person in one region to buy a DVD from anywhere would mean that those regional rights holders would otherwise lose money on their investments.
Surely this is quite a minor feature. I think it's unlikely that it helped their popularity "a ton".