The ferrule thing is real and here's what I think is driving it. Back when most trowels had wood handles, the tang was held by the wood itself plus a tight ferrule, and when the wood dried out and shrank you could just soak it or oil it and keep going. Now a lot of companies went to rubber or plastic overmolds, and the plastic flexes more than wood ever did, so all the stress goes right to that seam where the ferrule meets the handle. That's why the cracks show up in the same spot on every brand. A handle that can't dry out and shrink with the seasons will crack at the weakest point instead, and the weakest point is always that joint. I'd look for a trowel with a wood handle and a real pinned tang if you want the old lifespan back.