Opera used to have a built in RSS reader that was better in my opinion.

Some of the people behind Opera has built Vivaldi, which also contains an RSS reader. I haven't used it myself, but it looks promising.

Seems risky to rely on a browser as your RSS reader. I know you could always export your OPML file but not every reader seems to import/export that spec correctly

I have a feeling that it used to be much more valuable to send users to your site in the past, than today where a lot of traffic comes from search/ads/social media.

Perhaps it is time to revisit a distribution model, where the full content of the article is available for paid users inside the reader itself. The RSS reader would require a subscription and pay RSS feed providers a share of the subscription price. A sort of distributed spotify model.

I haven't used them myself, but it seems that services such as paddle.com takes care of the payment and tax compliance. There are probably similar sevices for logistics as well.

The thing is majority platforms like paddle.com don't supoort hardware products. I was looking at fastspring as well but hit the same wall. I will still try reaching out to paddle.com support to see if they will allow it. Thank you for the suggestion.