I have this Kripke model $M$:
$$ \begin{array}{ccccccc} \to & (p, q) & \to & (\neg p, \neg q) & \to & (p, \neg q) \\ & \circlearrowright & & & & \circlearrowright & \\ \end{array} $$
where $(p, \neg q)$ means “$p$ and not $q$” and $\circlearrowright$ is a self loop.
Now I cannot wrap my mind as to why:
- $M \vDash \mathop{\mathbf{A}}\mathop{\mathbf{F}}\mathop{\mathbf{A}}\mathop{\mathbf{G}}p$ is false in CTL;
- $M \vDash \mathop{\mathbf{A}}\mathop{\mathbf{F}}\mathop{\mathbf{G}}p$ is true in CTL*.
If you have a reasonable explanation for the above I might post a second analogous example which might disprove your intuition.