Diffeotopy group, Mapping Class group, Isometry group

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There are several closely related concepts on the symmetries or symmetry groups of the space.

My apology, but some vague imprecise definitions may be as:

  1. Mapping class group (MCG) is an important algebraic invariant of a topological space. Briefly, the mapping class group is a certain discrete group corresponding to the symmetries of the space.

  2. Diffeotopy group: The diffeotopy group D(M) of a smooth manifold M is the quotient of the diffeomorphism group Diff(M) by its normal subgroup Diff$_0$(M) of diffeomorphisms isotopic to the identity. Alternatively, one may think of the diffeotopy group as the group $π_0$(Diff(M)) of path components of Diff(M), since any continuous path in Diff(M) can be approximated by a smooth one, i.e. an isotopy.

  3. Isometry group: the isometry group of a metric space is the set of all bijective isometries (i.e. bijective, distance-preserving maps) from the metric space onto itself, with the function composition as group operation. Its identity element is the identity function.

These concepts are important and relevant for exotic $\mathbb{R}^4$, for example, we can ask: "Does every isometry group of an exotic $\mathbb{R}^4$ inject into its diffeotopy group?"

So my question here is aimed for a relation and interpretations between the definitions of Diffeotopy group, Mapping Class group, Isometry group?

For example, it seems that $$ \text{MCG($S^2 \times S^1)= \mathbb Z_2 \oplus \mathbb Z_2$} $$ $$ \text{extended-MCG($S^2 \times S^1)=\mathbb Z_2 \oplus \mathbb Z_2 \oplus \mathbb Z_2$} $$ similarly,

$$ \text{ diffeotopy group of $(S^2 \times S^1)=\mathbb Z_2 \oplus \mathbb Z_2 \oplus \mathbb Z_2$} $$

Are there general relations between the above Diffeotopy group, Mapping Class group, Isometry group?