The filter encouraged the driver to travel at 107 mph in a 55 zone. It doesn't matter who was holding the phone.
How do you figure? Let's accept the fact that there is a 100mph trophy, which appears to be in debate, but let's just accept it as true. Then snapchat encouraged users to go fast. Are there many legal and safe ways to go that fast? Yes. Plane, train, passenger on a racetrack (yes there are options for that), etc. It is not an achievement for going 107mph in a 55mph zone. It was not for going faster than the speed limit. It did not encourage illegal behavior. It encouraged, at best, behavior that is the users responsibility to determine a safe time and place to perform.
My fitbit encourages me to run. It does NOT encourage me to run into traffic. It does not encourage me to plow others out of my way so I can run on a crowded path. My scuba computer tracks my max depth, so is it encouraging me to dive deep? Sure, especially when combined with online dive logs. Is it encouraging me to go deeper than I know by my training to be safe for my training and equipment?
No. It is my responsibility as a human with a brain to determine when activities are acceptable. It wasn't a death toll counter or encouraging anything with no legal opportunity. It wasn't financially incentivizing illegal behavior (the equivalent argument to paying someone to punch someone else).
The driver is responsible for their actions. They drove a car at nearly twice the legal speed limit. That was their decision, and that responsibility is on them.