FWIW I own a Henry, and I had no idea the name was a play on Henry Hoover's name -- it's not manufactured by Hoover, after all, and it postdates the word becoming a generic term by a long way. I think the article's take on it is more likely -- machines branded Hoover were so ubiquitous in the first half of the 20th century that the term became a common word (the OED has cites for 'hoover' the verb with no capitalization or quote-marks starting in the 1940s), and once something is a common word it gets passed on to later generations regardless of whether the actual device in use is one from the company or not. (Though I remember in the early 1980s the hoover my parents had was indeed a genuine Hoover...)

But Henry is made by Numatic, not Hoover.

FWIW, Numatic is a British company, and not in the "Claims to be British but actually based in the Far East and doesn't pay any tax in the UK" way like Dyson.

Non shopping link: https://www.numatic.co.uk/products.aspx?r=4&sr=1

People call it a Henry Hoover in the same way they they call any sticky tape, sellotape.

Hoover is a brand name that has become genericised, a Henry is no more or less a Hoover than a Dyson is.

Here's a list of some others, Hoover is on the list

https://en.m.wikipedia.org/wiki/List_of_generic_and_generici...