> As for a delete operator, you can just roll your own struct based allocation framework that uses IDisposable to reclaim memory. But then you need to deal with all the traditional bugs like use-after-free and double-free and the like.

I forgot that there is built in support for this model using the MemoryManager<T> class [0]. A memory manager is an abstract class that represents a block of other memory, including possibly unmanaged memory. It implements IDisposable already so you can just plug into this.

The Memory<T> struct can optionally internally point to a MemoryManager instance allowing you to plug your perfered style of allocation and freeing of memory into parts of the framework.

There is a little irony that a MemoryManager<T> is itself a class and therefore managed on the gc-heap, but you can defeat this by using ObjectPool<T> to recycle those instances to keep allocation count steady state and not trigger the GC.

I have used this before (in the toy database i mentioned earlier) to allocate aligned blocks of unmanaged memory.

[0] https://learn.microsoft.com/en-us/dotnet/api/system.buffers....