Not at all! Wordpress' plugin is very good. My gripe is a more philosophical one; I'm realizing that ActivityPub isn't the best fit for a traditional blog. However, I can see WordPress becoming a really nice AP application in the near future (as soon as it gets the following working) for those starting today.
Kindle Fire is a different beast: they run Android AOSP modified by Amazon and usually has low-end specs. I'd not recommend getting one anyway — tied to Amazon or otherwise.
It's a shame indeed. Kobo used to sell their devices here, but they pulled out years ago. We also had a local bookseller that tried to face off Amazon, Saraiva, that released its own e-reader in ~2017, called Lev. (Probably a rebranded Chinese device; it was awful.) It didn't last. Right now, we have only Kindle devices for buying, and even that isn't complete — Kindle Scribe hasn't arrived yet.
You could share the links in other fediverse instances, couldn't you?