I think it is the lack of any tangible, first hand proof that this can actually work - paired with the reports of this actually not working, like:
Network charging when it should not.
Registers seem to be working, but not very well.
That’s all the core properties not working very well, and the team has not been very “Yeah we seen this and working on the fix”.
Couple those with missing all the marks on the Roadmap, having not named any partners and some heavy criticism from the long time believers.
And by saying all this, I don’t mean to be mean, just open a perspective where we are at this very moment.
Let’s hope it changes and we soon get some bugs fixed, partners announced, and something to do with the network.