Many flagships are moving to 128GB base storage and the iPhone XI may follow suite. Current models start at 64GB, the two XS phones don't even have a 128GB option - instead they jump straight to 256GB. Note that this reportedly covers both the premium iPhone XI and the more affordable XR model. Doubling the base storage will reduce the effort needed to fit your data into the base model, which is especially tricky as new iOS updates arrives and needs some extra room to install. The new iPhones - which we're calling "XI" for now - will have a square camera humps and this is what cases for...
Source: https://www.gsmarena.com/the_new_iphone_xi_phones_may_have_128gb_base_storage-news-37356.php