Sure, there are some recent exceptions. But nearly all words that contain vowel pairs like “ea” and “ai”, for example, represent a much older pronunciation regardless of the current one. Words like “hear” and “wear” would have rhymed at one point. Most words ending in “ed” would have had that syllable fully pronounced instead of reduced to a “t” sound.

That vast majority of words among all English dialects are spelled similarly and go back to the 16th century or thereabouts.