It may be a longstanding practice, but it's a foolish and aggravating one. Do you think HN's readers are so silly they don't understand claims made in headlines are not to be taken at face value?
The article advances a position and argues for it, which is reflected in the original headline formatted as a statement. It doesn't ask a question and then provide answers; the editorialized headline misrepresents the article's content.
EDIT: You've now rather spitefully changed the title to something that's even less representative of the contents—plucking a quote doesn't make it representative—and removes the intended allusion to recent conversations around the Google moat memo.
On the contrary, I changed it to the article's own statement of what it is about. (Note that it happens to be a question - in other words, the mod who put the question mark in the title was on the right track.) More explanation here: https://news.ycombinator.com/item?id=36328562.
Replacing a baity title with representative language from the article itself is just about the most common thing mods do on HN. If you think that HN is worth being a regular reader of, then you're benefiting from this practice whether you feel aggravated by it or not; it's foundational to this community.
I know people love to hate HN's title editing practices - I've been hearing about it for well over 10 years - but of all the things we do on HN this is the one I feel most confident about and am happy to defend until the cows come home. This may seem counterintuitive (how can the best thing be what people love to hate?) but there's a simple reason for that: people notice the cases they dislike and overlook the others.
I have no issue with editing click-bait titles in general, but specifically with adding a "?" where none is required and where it misrepresents the article's content. Your further title edit just strikes me as retaliatory and punitive; it does not encapsulate the article's position in the way the original did and is so uninteresting it's likely to discourage any further attention. You may not think the article deserves attention, but the users apparently disagree—no one in the thread has complained that it is a click-bait article, and people here have a hair-trigger for that sort of stuff.
The article advances a position and argues for it, which is reflected in the original headline formatted as a statement. It doesn't ask a question and then provide answers; the editorialized headline misrepresents the article's content.
EDIT: You've now rather spitefully changed the title to something that's even less representative of the contents—plucking a quote doesn't make it representative—and removes the intended allusion to recent conversations around the Google moat memo.