Sports Interactive have largely themselves to blame for failing FM Mobile sales.
The game gets next to no advertising or marketing compared to other versions. We hear nothing about new features and screenshots until about a week before release.
In press releases, FMM is generally a footnote with only a vague paragraph or two dedicated to it. In my opinion, that reflects SI's feelings about the title.
The FMM technical team is tiny compared to other versions, hence there's only so much development that can be done, resulting in some users feeling that the game changes little from year to year.
Piracy is an issue, but I don't feel they've done much to counter this and seem to have just given up in the hope they can shut down the game or sell up to the highest bidder.
I've loved FM for decades. I've loved FMM for almost a decade now. This decision is unquestionably a low point in my time playing this title. I have a Netflix account but am really in two minds whether to play next year's version.
SI have done FMM dirty for years imo, like an unwanted stepchild, resulting in modest sales and they are now trying to find a way out.
EVERY adult on the planet has a mobile phone. You can't tell me that there are less potential FMM users out there than there are full FM users.