"the players within the phone industry have similar privileges"
I suppose that would be true if we exclude all the electronics shops that could make a business charging a small fee to unlock phones.
"I could point out that they also bear the burden of paying billions up front for lease of spectrum"
Which actually helps the cell companies more than it hurts them, since it basically rules out a large number of potential competitors. A coffee shop can run a wifi network, but that gets extremely limited bandwidth and extremely limited power. Amateur radio operators have fewer restrictions on power, but are completely tied up in other regulations.
Large areas of the United States are served by only a handful of cell carriers, whose service is overpriced and mediocre at best. There are two possible solutions to that situation: abandon market-based solutions and create a monopoly that is heavily regulated to protect consumers from abusive practices, or embrace market-based solutions and reduce the barriers to competition (say, opening cell phone bands to unlicensed secondary users with established rules for settling interference disputes). Right now, we are not really pursuing either strategy, and in the mean time we are falling behind other countries in terms of wireless deployment.
"You want to unlock the phone overseas, then do it overseas where you won't be subject to US law"
OK, sure, but that just means that American businesses that might unlock phones (say, businesses at international airports) cannot exist. It still helps the cell carriers' business model, just not as much as it might have (it reduces the convenience and introduces potential language barriers).
"You want to have two contracts on the same phone, the second one is going to be month-to-month by definition because the second carrier has no property interest in the phone"
Neither carrier has a property interest in the phone. Nobody is charged a fee for breaking their phone while under contract; they are expected to just buy another phone.
"you can easily get out of your contract by paying the ETF."
So what? That is not the issue. Nobody is suggesting that people should be able to terminate their contracts without paying a fee. The issue is whether or not people will be able to unlock their phones, which is completely orthogonal to the issue of contracts.