Everyone says different things because earnings here are highly individualized. There is no one size fits all earning per hub that can be applied to anyone on HP. If $1.50-$3.00 per hub per month is your personal goal for earnings you will get there with a lot of effort and time. For instance, one hubber may get 41,000 views in a month, another may get that many in a year and they likely will not earn the same amount. Some hubbers activate Amazon and Ebay earnings and others don't. Some market and promote themselves and use SEO and others don't. Create your own plan and goals and strive to accomplish them.
This is not a get rich quick income source. Some write here for fun and do not make any effort to earn money. It's your goals and plans to reach them that count. Don't worry about an average because there truly is none that applies across the board. You will need to promote your hubs, perform SEO or hire someone for it and you will need to be active here. The quality of your hubs and topics must be good.
Earnings are highly individualized and dependent on many factors such as the writer and their level of activity, their promotion of their hubs, their topic(s), the type of writing and having new content that preferably isn't easily found elsewhere or is at least presented in a way that holds the readers' interest. Avoid writing about things that aren't in demand or have been written about heavily.
I have been here for nearly 3 years now and my earnings have consistently been going up. I see it as an additional stream of income that is residual and will continue to be cultivated and grown with effort and time. Speaking from my experience I would say that you will not earn much money out of the gate and it's best to think of HP as a stream of income, an addition to other income sources or a side gig as it will likely take years for you to hit your own highly individualized earning stride and earnings goals.