What part was inaccurate? You're saying it's reasonable that drivers who don't drive to Boston object about a new gas tax but I say it's unreasonable because a public good should not be funded based on usage. It should draw from the entire population pool. Tell me how it would be feasible to then fund every public good based on who uses them.
Also, you can't find a solution without first identifying the problem and the problem here is that there are people who don't understand how public infrastructure are funded and managed and think that they should only pay for something they use. That's not how states, cities, and towns work. People don't exist in vacuums. And no matter how you "frame" it, if people feel like they are not going derive any direct benefit from a project, they are not going to agree to it.
And in your case, those same people who don't drive into Boston will never agree to it because the fact is, they actually aren't going to get much benefit from expanding public transit in Boston (for example people working in Springfield won't get any benefit whatsoever). However, the purpose of a tax is to fund different projects that benefit specific areas so while one project may not benefit a town in the west, a separate project could but this can only happen if everyone contributes.
If these people feel that a higher gas tax are targeting drivers unfairly, then get rid of the gas tax and just raise the tax on everyone.