>It's missing some important feature, like persistence?
Hard to answer, considering....
>It's had very little advertising?
Personally, I've never heard of it and have no idea what differential dataflow is. Maybe I've done but I never gave or discovered a name for it. I don't know what spark or kafka streams are. Maybe because I've never had a use case for those that wasn't satisfied by a tool that was "good enough", or, more likely, I haven't come across anyone recommending those on projects, because they also don't know what those tools are. I would have never known what RabbitMQ was if a coworker never suggested we use it to build queues, and it turned out to be cumbersome to use and 100x more complicated than writing a stored procedure that turned out to be "good enough". Most tools fall into that space where they are marginally better in some regards over "good enough", but not better enough to accomadate for the learning curve for other developers, changes in maintenance or design, cost, etc. Advertising is pretty general and it's hard to say if which of these it's doing wrong, and depending on their market none of these might be wrong for them, just the potential market is content with "good enough" and have no need to search for tools like this.
>Rust is intimidating?
I'm not sure what the stats on Rust are but I don't think its that popular for business developers to where you could point to it for the reason a tool has failed the adoption phase
Hard to answer, considering....
>It's had very little advertising?
Personally, I've never heard of it and have no idea what differential dataflow is. Maybe I've done but I never gave or discovered a name for it. I don't know what spark or kafka streams are. Maybe because I've never had a use case for those that wasn't satisfied by a tool that was "good enough", or, more likely, I haven't come across anyone recommending those on projects, because they also don't know what those tools are. I would have never known what RabbitMQ was if a coworker never suggested we use it to build queues, and it turned out to be cumbersome to use and 100x more complicated than writing a stored procedure that turned out to be "good enough". Most tools fall into that space where they are marginally better in some regards over "good enough", but not better enough to accomadate for the learning curve for other developers, changes in maintenance or design, cost, etc. Advertising is pretty general and it's hard to say if which of these it's doing wrong, and depending on their market none of these might be wrong for them, just the potential market is content with "good enough" and have no need to search for tools like this.
>Rust is intimidating?
I'm not sure what the stats on Rust are but I don't think its that popular for business developers to where you could point to it for the reason a tool has failed the adoption phase