Yo
“In other words, what social pressures are causing him to doubt his previous appellation of the country?”
He joined a new club. To be a full fledged member there’s a uniform, a secret language etc. He wants to be s member so the BT wears the velvet yarmulka and says Eretz Yisroel.
I don’t get the problem.
If you want to be a member you can do these things too.
If you don’t want to be a member so dont do your own thing and let us have our club