After I noticed Firefox has removed the Pocket branding but kept the Pocket stories, I also noticed the settings screen on the homepage no longer lets you disable sponsored stories or links.
Firefox 115:
Firefox 139:
You can still remove these advertisements, but you have to leave the homepage and dig through the settings to find that option.
But how much of their resources did that represent? 1%, 10%, 50%? This being a problem really depends on that number.
They are trying to find ways to earn money independent of Google royalties so they can keep making massive FOSS projects, that compete with FAANG technology, independently. For me all the community troubles and failed projects mostly show how hard this is.