That's one of the two major issues arising from the major restructuring of the MBTA's finances two decades ago. The other is that it's funding was set based on the projected growth of state sales tax revenue, which is responsible for most of the MBTA's funding. However, sales tax revenues grew much more slowly than projected.

Putting up barriers would be a huge undertaking for the MBTA as it requires the trains to stop in the exact same spot every time they pull up to the platform. This would require replacing the existing signaling system and train cars. Much of the T uses an outdated analog signaling system, which is only now being replaced with a digital system. Likewise much of the T's rolling stock is decades old and won't be fully replaced for another decade or two.

Maybe not. Bernie Madoff got a 150-year sentence for his financial crimes.

The New Yorker published a good review of the bizarre experience of attending a Shen Yun performance.

https://www.newyorker.com/culture/culture-desk/stepping-into-the-uncanny-unsettling-world-of-shen-yun

They tend to to tailor their message to the political leanings of the local audience, so a performance in the Boston area is unlikely to include their stances on gay and interracial marriage, atheism, evolution, and medical science.