The fault with that headlines has little to do with a small dedicated following. Apple isn't a "small" PC manufacturer when it's got more than half the shipments of the largest manufacturer. The real fault with that clickbait is it ignores Apple desktops had an enormous boon with people migrating to M* based desktops and they aren't ready to upgrade yet while simultaneously ignoring shipments are still higher than pre M* Apple desktops. Besides that, clickbait articles about other things other companies do don't even say anything about this topic.
Again, focusing on how the usage share is abysmal compared to competitors while consistently shrinking down to where it is over the last decade lets you easily see why this particular headline isn't clickbait. Even with millions of users, Firefox having such low usage share, especially compared to alternative competitors, is a risk to its main funding source. This is a problem for an organization like Mozilla which makes very little from its users vs one like Apple which has become the most valuable in the world through the exact opposite.