Unfortunately, you are not correct.[1] Recording police in a public place-- sure. Otherwise, eh, at best you're over-extrapolating (and ungenerously!) from your local circumstance.
Okay, wow -- I stand corrected. I will edit my comments. It will take me awhile to wrap my head around Massachusett's-style state-level restrictions. While I wouldn't personally expect this to survive a Supreme Court adjudication, apparently there exists no Supreme Court ruling either upholding or striking down the prohibition on secretly recording oral conversations in public.
The key element here that everyone seems to be confused about, is secret vs non-secret.
If you have an obvious security camera, or an obvious camera that normally would record audio, and you’re in public waving it around and it records audio? You are not secretly recording audio.
Same if someone is standing next to a obvious and clearly visible security camera which normally could also record audio, also, not secretly recording audio.
A hidden mic in your jacket, or like in that case, hiding the camera under a jacket? That is hidden recording.
The general rule of thumb is - if everyone can clearly see what you’re doing, it’s not secret.
[1] https://www.dmlp.org/legal-guide/massachusetts-recording-law