A majority of the feeds I subscribe to do not include the full text in the feed themselves which is one of the main reasons I use Miniflux which has an option to fetch the full article text and works very reliably. Of the more than 150 feeds I am subscribed to, I think there are fewer than 5 that Miniflux is unable to fetch the text for. Miniflux can also connect to Wallabag to quickly save pages to it using the full text. That is great because Wallabag is often unable to fetch text directly on its own.
I’m also a happy user of Miniflux and that specific feature. I still sometimes want to click out to the article easily to double check if it feels like something didn’t parse correctly. Rare but happens.