The question is then what phone exists that is immune from this? A flip phone? A Nokia 1011? I might be completely misinformed but seems like SIM card and the underlying OS is vector. What happens if I use a cell phone from late 90s and early 2000s? What is there to hack with those flip phones? JavaME over the wire? What if the cell phone dates even further?

Legitimately curious what options is there. Could If you are someone of interest then it seems like having a smartphone is an automatic liability. What then solution is possible since sending and reading a simple text message is enough to escalate privilege?