"Much" refers to something not countable, like "much more milk", and is used without plural, "liter" is countable such that you could say "many more liters of milk" (note the plural of liter). So while I'd say the latter is more correct according to grammatical rules, if both are common, both can be considered correct, as rules are often rewritten to adapt to the way the English language is used.
Every language is complex, wtf are you smoking? If anything I'd say English is the best choice for a global standard because of how adaptible it is and the fact that it's already the global common language for a bunch of industries. Reversing that will be challenging if not impossible
That was my reasoning, which is correct in my native language (Spanish: "muchas más imágenes). That's why seeing more results for "much more images" suprised me.