It might work that way, actually .
Just because the phone is encrypted doesn't mean there's not an exploit that makes it easier to bypass or extract the passphrase. Celebrite is unfortunately pretty good at attacking out of support phone and breaking into them.
Use a modern, supported OS on a device put out by a trusted vendor and you're probably ok. But old software/hardware makes it much easier to bypass.
A pure bred Akita named Misha. She was a beautiful and nice dog that some neighbors down the street has. I loved that dog and pet her whenever I went by and she was out.
One day, after walking one of the little neighbor girls to school, I stopped to pet her and she got excited and in the process of licking my face, got a fang caught in the bridge of my nose, ripping it open from top to bottom. She didn't mean to, but it happened and I had to get a bunch of stitches (and discovered that they can't numb cartilage), so the poor girl had to spend the rest of her life in a small high-fenced yard. I hated it, but I completely understood the owners wanting to make sure they didn't have to put her down over a mistake.