It's never been part of the Mauritian state. If we're to propose restoring the old colony of Mauritius under its original boundaries, that would involve putting other islands, including an independent state (Seychelles) under their jurisdiction.
I do agree it was an abuse to throw out the inhabitants. Realistically, there's not much prospect of any of them returning to the islands in their lifetimes.
From a strategic point of view, I would think that democracies in the region really should recognise the importance of the military presence and the guarantees that the British territory status offers. Instead, I expect, for some it's a matter of national pride and for others it's placing notions about decolonialisation ahead of a realisation that this is a tiny-scale situation with wide-ranging benefits.