The issue is that people aren't being arrested for committing crimes.

I used to live in the area where Boylston and Washington meet and I had a great view of the intersection where CVS is. I've seen so much crime happening in broad daylight that never gets addressed.

My favorite example is drug dealing in the elevator at the Chinatown T stop. A few guys would walk inside and a few would stand outside to prevent people from using the elevator. I once saw them legit turn a guy in a wheelchair away from using the elevator. There's also a row of blue bikes there, and the criminals would just sit on those bikes all day dealing drugs. The police are well aware of this but they never make arrests. At best, maybe one day a week a couple of officers would stand on the corner for a few hours.

People feel emboldened when they brazenly commit crimes with no consequences, and it will only trend worse unless something is done to address it.

Yup, this is definitely a big factor.

I lived in DTX/Theater District for many years and have noticed crime get progressively worse in the last few years. I've talked to a few officers and basically they've given up on making arrests because the DA rarely chooses to prosecute. Instead these cops just sit on their phones in their squad cars all day.