It's a plain link--it's not an ad.

> an apparent undisclosed ad for Nord

What evidence supports the link referenced being an advertisement? I'm not seeing any referral, tracking, or any URI parameter data at all that would support the claim, and this seems to be their only instance of referring to it — where, in this 'state of the union' helpdesk-style article, one or more such 'VPN provider' links seems particularly relevant to visitors. (I do not use whatever this company's products are and have no opinion either way on them aside from mistrusting the claim presented here.)

One time I saw someone trying to hide an Amazon affiliate link in a post by putting the link text as amazon.com/dp/12345 but the link was amazon.com/dp/12345/ref=tracking. There's no affiliate link for Nord here but it's weird to use it as an example over better options: https://www.privacyguides.org/en/vpn/