The Filter seems to be a low quality advertising column.
Ereader best buys selected by a self-appointed expert.
https://www.theguardian.com/thefilte.../best-ereaders
I'll leave others to comment, except it's only really inaccurate by omission.
Note the The Guardian has USA and Australian editions as well as the UK, and is also distributed in Ireland, but not a "fake" Irish version like the UK tabloids.
The Guardian are great fans of Apple, but Apple don't do an ereader (too niche and even the Apple Watch is a surprise).