Rav Moshe Feinstein held that we can’t apply tinok shenishba status to someone who lived near an Orthodox community and was aware of religious Jews. (Even if he didn’t grow up frum.)
Igros Moshe OC 5:28 , Igros Moshe EH 1:82:11 Igros Moshe EH 2:20 and OC 1:33.
Rav Ovadia Yosef held similarly that it depends on whether they were familiar with a Torah community. In practice that means non-religious Israelis and “in town” Americans are not considered tinokos shenishbau.
Rav Ovadia Yosef (Yabia Omer OC 10:55) and Rav Binyamin Zilber (Az Nidbaru 9:55).
Rav Shlomo Zalman Auerbach held that non-religious Israelis are not considered tinokos shenishbau and that the they are mumarim.
Halichos Shlomo Pesach pp. 326-7 and Madenei Shlomo p. 27