As it turns out, you shouldn’t mod your Steam Deck console with a physically bigger solid state drive (SSD) because it “will significantly shorten the life” of the system, according to one of the device’s actual designers at Valve. The warning comes after a mod began making the rounds showing a larger form factor SSD installed in the Steam
Source: Hot Hardware – Valve Designer Warns Modding Steam Deck With A Larger SSD Could Cause Serious Issues