I don’t think anyone who understands market share thinks that a drop in market share means fewer users. But it does mean that your product has stagnated and commercial interests are going to be focusing their energy elsewhere where it can have a more outsized ROI.
A constant market share as the pie grows is great - it means your attractiveness as a platform is keeping up with overall growth. If someone needs a 2% growth to edge out competition, targeting Linux could be valuable. A shrinking market share means I should invest elsewhere. Linux has remained niche because you need to get about 5-10% to warrant commercial interests because there’s a non 0 cost porting to Linux and providing some level of support. Also your potential customers have to spend money which is less clear from these numbers who the Linux community fares vs others. For example iOS customers tend to be more valuable than android because they are typically higher income, there’s a lot of them in terms of market share and absolute numbers and spend more money on the App Store / in app than the typical android user.
A constant market share as the pie grows is great - it means your attractiveness as a platform is keeping up with overall growth. If someone needs a 2% growth to edge out competition, targeting Linux could be valuable. A shrinking market share means I should invest elsewhere. Linux has remained niche because you need to get about 5-10% to warrant commercial interests because there’s a non 0 cost porting to Linux and providing some level of support. Also your potential customers have to spend money which is less clear from these numbers who the Linux community fares vs others. For example iOS customers tend to be more valuable than android because they are typically higher income, there’s a lot of them in terms of market share and absolute numbers and spend more money on the App Store / in app than the typical android user.