send as SMS. Once he does that, no problem.
I had an older iPhone that was having the same issues and ended up upgrading to the 16. Of all my siblings and spouses, my sister is the only one without an iPhone. Texted her to test and first time went through on new phone. Next time same stupid issue won't go through. That is when the option for SMS came up. Clicked on that and now no problem.
I have an iPhone and agree with you in some cases that Apple is stupid to not play nice with other brands. Example our family text group we can't add or delete someone because of my sister and her non-Apple phone. Can't even name the chat. She can do that no problem, which to me is stupid because I blame Apple for being the one that doesn't want to play nice.