I think the Materials Voice booth is an excellent idea to bridge the gap between policymakers and scientists. In this day and age when many often grow complacent and place faith in "keyboard activism", many put blind faith that something as simple as signing an internet petition is enough to realize change. It can be a chore to contact one's local congressmen or senators about concerning matters of science and science funding/policy, despite the fact that this is the most accessible, personal, and direct way for scientists and civilians to communicate with those in power . While the Materials Voice booth certainly makes it easier to write a letter to many lawmakers at once, I'm skeptical about the effectiveness of this approach if the same pre-drafted letter is sent to them a thousand times. Not all members of Congress are driven by the same things, so I hope anybody that is sending a letter takes some time to personalize the letter to inform them about issues that concern you and similar stakeholders and suggestions for what can be done differently. Otherwise, writing letters to lawmakers devolves to being no more effective than a petition.
As scientists and engineers, I feel we often criticize many lawmakers for their ignorance and close-mindedness. But perhaps some of us have personally tried to correct that ignorance, so do we have a right to criticize? Even a good letter may not completely bridge the rift between lawmakers and politicians, but if enough scientists write to them regularly it can be a good start. If you haven't already, you can stop by at PCC, Lower Level, Hall 5, Exhibit for more information!