You don't, but it has important implications for developers. 1T SRAM has a much lower latency than normal RAM. It meant the developer would be less likely you hit the
memory wall problem or at least they wouldn't have to do so many work arounds. It also means the GC and Wii are architecturally very efficient machines getting more done per clock. It worked well for the GC, but the Wii having not much under the hood in the first place being efficient with less still meant you had less to work with.
Unfortunately 1T SRAM is more expensive than it's DRAM counterparts per MB, but way cheaper than other SRAMs. It meant you can have fast responsive memory, but not much of it. From the looks of it, Nintendo has re-prioritised the need for more RAM. While it will take an efficacy hit, it will more importantly bring the programming environment more inline with everybody else and help provide the extra RAM needed to run both the TV and the tablet(s), something you just can't program away(You can just buy more RAM, but Nintendo's a cheapskate and it can get expensive quick). DRAM somewhat compensates for it's slowness by providing a lot of bandwidth instead, so you can waste some of it pre-ordering for things you don't need ahead of time instad of waiting for it to arrive.