https://www.heddels.com/2018/05/all-the-shoe-constructions-around-the-world/
Blake stitched shoes are sewn through the sole, upper, and footbed. With a leather sole, they're bound to get water inside if worn in extreme conditions. There are basically tiny holes through the sole all the way into the inside of the shoe.
If you have a blake stitched shoe (or a handsewn) with a leather midsole which has a rubber sole cemented to it (ie, the rubber sole is not sewn through), it would be just fine in wet weather. The holes are covered up.
Blake stitched shoes are sewn through the sole, upper, and footbed. With a leather sole, they're bound to get water inside if worn in extreme conditions. There are basically tiny holes through the sole all the way into the inside of the shoe.
If you have a blake stitched shoe (or a handsewn) with a leather midsole which has a rubber sole cemented to it (ie, the rubber sole is not sewn through), it would be just fine in wet weather. The holes are covered up.