Breaking the 7 GB limit counts more
I'm still not sure why SIM-locking matters, but I got a free smartphone from NTT Docomo for about 800 yen/month over the two-year contract. I actually felt kind of bad about it, even though I didn't make any of the rules. It is quite likely that my loophole is somehow related to regulation by the Japanese government, but it still feels like a violation of the Golden Rule. In the Kantian canonical form, if everyone did it this way, then the system would obviously not work. Yes, I had to agree to a two-year contract that would have cost much more, but NTT's own rules allow you to call up the next day and cancel everything except for the basic phone service. There was a nominal one-month penalty charge, but what actually hurt in a financial sense was that NTT had recently canceled most of their incentives for changing from another carrier.
The problem I faced was the 7 GB limitation. I don't need the big speeds of LTE, but I want lots of data. I was actually quite satisfied with unlimited data under 3G, but that was offered via a different company. However after Softbank acquired that company (for their bandwidth), they basically rendered that option unusable. After a lot of rather tedious research, I settled on the solution of a NTT phone without ANY data plan, and WiMax for the unlimited data (and excessive speed). The 7 GB thing is apparently NTT's policy to push people to buy fiber for their homes, and I absolutely don't need a fiber at home. However, I used 50 GB of data last month, and 7 GB still looks like a joke to me.
I want to make a prediction that things will get better, but then you have to ask why? NTT certainly isn't threatened by the competitors, though I'm unsure why. Perhaps KDDI and Softbank have been threatened with total war if they dare to offer unlimited wireless data?
(By the way, KDDI might have a similar loophole, but the basic cost is more like 1,000 yen/month. I nearly went that way, but the NTT salesman at Bic Camera was slicker.)