The MINI SSD card is not and may never be a formally ratified standard, but it is intended to solve a real problem for portable gaming systems -the need for fast storage that games can load with speeds that approach from an internal SSD, without users taking their own systems apart to perform upgrades.
Why are games actually getting so big?

Large storage, small size.
Credit: Biwin
An analysis of 2023 from TechSpot suggested that the game size had increased with an average speed of approximately 6.3 GB per year between 2012 and 2023 – gams that are more than 100 GB are not the norm, but they are not difficult to find. Part of that increase comes from improved images and the textures with a higher resolution that are needed to make games look good on 4K monitors and TVs. But TechSpot also noted that the storage requirements for narrative heavy, cinematic heavy games such as The last of our part 1 Were just as well driven by audio files and support for multiple languages.
“In total, almost 17 GB of storage is needed for [The Last of Us] Data that is not related to graphics, “wrote author Nick Evanson.” That is bigger than every entire game from our Monster 2010! This pattern was consistent in almost all the games of Godzilla that we have investigated that with countless cinematics, extensive speech and considerable localization were usually much larger than the rest of the sample in a certain year. “
For another prominent recent example, consider the installation sizes for the Mac version of Cyberpunk 2077. The version of the game on Steam, the Epic Games Store and Gog runs around 92 GB. However, the version that is available for downloading from Apple's App Store is no less than 159 GB, just because it includes all the voice -overs of the game in all languages it supports. (This is due to the rules of App Store that require that apps have included all possible files when they are submitted for assessment.)
It is clear that there is a need for fast storage upgrades for which you do not need to fully dismantle your console or PC. Whether it is this new “Mini SSD”, a faster iteration of MicroSD Express, or another non-sent storage layout can still be seen.