For the purposes of compared privacy*, security*, anonymity*, and so on, how difficult is it for bad actors to phreak a landline as opposed to a smartphone or other mobile?

Furthermore, how much more info would be gathered from a compromised smart- or even dumbphone as opposed to a landline?

[RANT]
Also I was reminded one shouldn't bother bringing stuff up like this to non-tech/-security types as I just had to respond to my dad's "we are never going to be able to get away from being tracked / no matter what you do, someone will know what ur doing / landlines can be tapped into easily / you're pissing into the wind" (surprised I didn't get the tired old "if you're doing nothing illegal what's the problem?" with "We'll never get away with cars and homes being broken into, but we still lock our doors don't we? / We'll never get away from accidental pregnancies, but we still use birth control, right? / And no matter what you do, you'll eventually die of old age. / Gonna get sick anyway so why bother with health insurance? / Gonna have to go outside eventually so why live in a home or apartment? / Gonna get hungry anyway so why eat? Gonna get thirsty anyway so why drink?" SIGH, this has to be a named fallacy since it's brought up so, so often!!
[/RANT]

* Of course we know phones are a joke when it comes to these, especially anonymity, but comparatively between the two...