Not misleading and fairly standard practice. There is no value starting at 0 when the lowest device tested is 55, all you'd do is shift everything to the right or make it smaller and harder to see the distribution (which is the whole point showing the distribution from 55 to 123).

As long as the graph goes up in consistent increments (in this case 10) and shows that all these devices could move to the left (i.e. get quicker than 55) I'd say the graph has done its job.