Difference between Array reshaping and MArray/SizedArray reshaping

Modifying a reshaped array modifies the original array as well but it doesn't do that with MArray or SizedArray (a copy is created instead):

julia> vm = @MVector ones(4);

julia> vmr = reshape(vm, Size(2,2))
2×2 MArray{Tuple{2,2},Float64,2,4} with indices SOneTo(2)×SOneTo(2):
 1.0  1.0
 1.0  1.0

julia> vmr[1] = 12
12

julia> vm
4-element MArray{Tuple{4},Float64,1,4} with indices SOneTo(4):
 1.0
 1.0
 1.0
 1.0

Since we now have SizedArray that can wrap any AbstractArray, this could be fixed relatively easily. Is this something worth fixing before the 1.0 release?

Reproduce the Julia REPL example for reshape on MArray and SizedArray, then trace the reshape entry points and storage behavior for these types versus ordinary Array. Determine the intended aliasing behavior and add regression coverage showing whether reshaped mutations affect the original; done means the behavior is consistent with the agreed semantics.