It's more of a cost benefit analysis as the author pointed out. When so much of valuable content is surfacing in hackernews and other streams, it's not cheap, rather a wise decision not to spend money.
We could automate the link posting process. Here is a thought, create a form which accepts the input of link details, stores in some place and ur website reads and displays from there. Submitting a form could be simpler and can be done from any device.
Yes and no, abstractions dumbed down things for common users. But there are and will always be a set of power users who get into the details. Power users are the ones who abstract in the first place and abstraction is not a one time process. Abstraction keeps evolving too, hence there are going to be power users who know the capabilities and support in the evolution. This is any how stream works let alone software. There is no need for everyone to be a power user.