What exactly is "unethical" about not investing tons of money in something that isn't going to yield the kind of profit your investors want? People act like Verizon and AT&T have a moral obligation to spend money on telecom infrastructure as a public good at minimal price above cost.

Having agreed to make such an expansion, and having been paid for it, it is unethical to choose not to without returning the money.

They're given public rights of way and tax write offs to build their infrastructure. So yeah, they have a public duty.

Well, investing tons of money in lobbyists to pass state laws to prevent the deployment of municipal broadband utilizing public tax monies and breaks, is considered unethical (at least to me).

So, not investing in infrastructure is not the problem, but preventing others from doing so, is scummy.

They do not want to invest AND they don't want to compete.

If so, it was a massive mistake on their part. AT&T and Verizon lost the ISP market to cable companies in the mean time.

which is actually better than spending billions and then losing the ISP market to cable + other ISPs using wholesale.

It's actually a rational move. Title II prevented them from competing effectively with the companies that were not under Title II, hence the rational decision not to invest in competing infrastructure.