Zinedin Zidane is the coach who has the most experience in training big club like Real Madrid and Zinedin Zidane has already made a name for himself his good name at the club so it is not impossible that Real Madrid will recruit him again.
However, if Real Madrid wants to try to recruit another coach, I think the one who is more suitable is Xabi Alonso, but it seem that Xabi Alonso cannot yet coach a big club like Real Madrid and Xabi Alonso still wants to improved his coaching performance while he is still at Leverkusen.
I suspect that Zidane will return to Real again if Real gets Mbappe (or Haaland). After Zidane won the Champions League three times in a row, he definitely doesn’t want to lower the bar, so he’s only waiting for a big project, he can’t lead the French national team because Deschamps gives results, so if Real tries hard, they can convince Zidane next summer. But if, as they say, the sheikhs buy Marseille, then I think that it will end up there.
Back to Xabi Alonso whose career wants to develop and Madrid's offer is his opportunity to make that happen. In terms of convenience, in this case, Xabi Alonso can respond more quickly.
I doubt that the wife really is an issue if everything else would be perfect for him, but Alonso could indeed be a competitor for the position as a coach at Real Madrid. Because I can imagine that Real Madrid would like to have the position be occupied long term with a trainer who has great prospects for the future. Xabi Alonso could be that kind of guy while I doubt that Zidane would commit to a long term engagement with any club except for the national team. He prefers to have flexibility and freedom and he knows that he will also be measured by his own achievements, which means not winning the Champions League would immediately raise questions even though it's unrealistic to win it all the time.