Is Row HQ a client or your own product?
My own. The search plan, the content system and the six-country setup are all mine. That is why this page can show the whole picture, not an edited slice. Every number here comes from a source you can check: Search Console, the live SERP, or the site's own sitemaps.
Why launch in six countries rather than one?
Rowing is the same sport everywhere. The buying is not. UK clubs need British Rowing affiliation. US clubs do not. Everyone wants to pay in their own money. One global page would have been weaker in all six markets than six local ones.
Does hreflang actually change anything?
It decides which of six near-identical pages Google shows. Without it the versions compete with each other and Google picks one, usually the wrong one for the searcher. With it, a club in Auckland gets the New Zealand page with NZD pricing. The tag does not win the ranking, it just makes sure the right page collects it.
Why build thirteen free calculators?
Rowers look up their split, their drag factor and their 2k far more often than club software. The calculators answer what the sport asks every day. Search "drag factor calculator" and Row HQ comes first. Concept2, who make the machine, come third.
Could the same approach work for my product?
If your category has a small head term and a large surround of daily questions, yes - that is the same shape. It works less well where the buyer only ever searches one commercial phrase. The first call is usually enough to tell which one you are.