You're gaining a more efficient CBP, enforcing visa rules and avoiding overstays like they do now, just with higher accuracy. Now if you want to argue that visa classes are silly and the US should just let anyone come in for whatever, fine, but that's a totally different argument.
And yes, it's possible that this isn't worth the gains to CBP. But the US is pretty powerful and can force quite a bit of crap on people without getting too hurt. If it stops, it'll most likely be from efforts from e.g. Facebook lobbying against it.
Business travelers have little choice. A lot of migrants have no choice (the benefits of US residency far outweigh the inconvenience for most people) -- we can test this out by looking at how many Mexicans or other Latam folks stay in the US vs, say, Canada over the next few years (confounding that is Canada removing visa requirements for Mexicans). Tourism might be hit a bit, but I'm unconvinced this is a big enough deal for people to rethink their entire vacation plans.
Enforcing visas through violating privacy seems like a good enough argument against this practice to me. What you're also gaining is a precedent to enforce more searches that look through not just your public life, but also the intimate parts that the government really doesn't have much business in analyzing.
Power grows? I'd like to know what contraband CBP expects to find on electronic devices. At any rate, they can only ask citizens to comply, not force them.
And yes, it's possible that this isn't worth the gains to CBP. But the US is pretty powerful and can force quite a bit of crap on people without getting too hurt. If it stops, it'll most likely be from efforts from e.g. Facebook lobbying against it.
Business travelers have little choice. A lot of migrants have no choice (the benefits of US residency far outweigh the inconvenience for most people) -- we can test this out by looking at how many Mexicans or other Latam folks stay in the US vs, say, Canada over the next few years (confounding that is Canada removing visa requirements for Mexicans). Tourism might be hit a bit, but I'm unconvinced this is a big enough deal for people to rethink their entire vacation plans.