French verbs are conjugated depending on the subject's person and number (ex. je parle, tu parles, il parle, etc.) However in spoken language most of these sound the same anyway because the end part of the word tend to not be pronounced (this isn't the case for vous parlez and nous parlons, though).
Since when does this happen and why? Apparently it doesn't happen in other Romance languages. Why is the loss of sound and inflection in speaking not followed by in writing? Is it expected that in the future the conjugation will be much simpler, like in English? Or has there been evidence that it is currently happening?