I agree with this. I have been using Pocket way before it was integrated into Firefox and tbh the extension was much better - seems like after tying it to my Firefox Sync account I have to relogin every few days to get the "Add to Pocket" button to work. The extension just remained logged in and stuff worked.
I'm intending to switch over to self-hosted Wallabag though, for privacy and efficiency reasons.
Personally find Instapaper to be better though. I got annoyed by the in-your-face-upgrade mentions. Instapaper also has slightly more customizations in the free tier and looks nicer overall.