The Foxit PDF Editor product page is one example (not the worst by far). It suggests prominently that you have to buy an annual subscription ($109 to $159 p.a unless you can live with the cloud option for $59 p.a). Microsoft Office 365 Personal is $69.99 p.a including 1TB cloud storage.

https://www.foxit.com/pdf-editor/

The one-time license option is hidden away in a product comparison table (and linked to in a few other far less visible places).

Nitro, the other PDF editor you mentioned, appears to offer only a one-off purchase:

https://www.gonitro.com/pricing

But it says "for Windows" and at the top of the page, there's a promotion saying "Get up to 1 year subscription - free when you switch to Nitro". So there is a subscription after all?

If you keep scrolling down to the FAQ and there's a question asking:

"Is Nitro available as a subscription or a one-time purchase?

Nitro Pro, ideal for individuals and small to medium sized teams, is available as an annual subscription."

No mention of a one-time purchase option. So which is it? I'm confused. Is this "one-time purchase" a perpetual license or does it stop working after a year?

These are certainly not the most egregious examples of pricing shenanigans. But given the recent history of companies going subscription-only, this is enough uncertainty for me not to buy.