Supply and demand. The value that Snapchat provides to individuals and advertisers is tiny but huge in aggregate. There just isn't the same volume of people with conditions like Alejandro's and the variety of problems people face make the economics especially challenging within a free market.
However, I feel we're at a really exciting point in history. With open source software and hardware, the work that a single person like Alejandro's dad does can be provide value and spread like neither before. Advances in tech that seem to provide only minimal value to us allow for engineers to be trained, gain the skills and have the know how to make a significant difference to people like Alejandro.
The challenge is how can we channel as much of the value and tech created by the free market into problems that the free market struggles to solve, like disability and assistive technology. Open question!