First, you assume that this behavior isn't well understood, well documented, and even expected in my organization and our corner of the industry. The reason FreeRTOS has an allocator that doesn't free is because it's standard behavior in embedded systems with hard time requirements.
Then you guess that we've taken no precautions against some future developer not having this knowledge. The allocator in question asserts if the user tries to free to avoid the very scenario you describe, and attempting to use newlib's allocator asserts with an explanation of why it's unused.
Technical debt is an issue I take very seriously, and I work hard to document the design decisions we've made. Choosing to use a tool that's designed specifically for our use case, instead of taking the time to set up a general-purpose allocator with overhead we don't care for, is hardly a debt that needs to be paid off.