Although the video sounds like an ad for Firebase, I 100% agree with the idea that creating and managing native apps for multiple platforms is not worth the effort for most businesses.  

Whenever I have said it's not worth the time and effort, there is always resistance with the default, "Mobile devices have over taken desktop... .... You have to have a mobile app today... ....yada yada yada"

There are enough platforms and libraries that can give you a native like experience at a fraction of the development time and cost.  Also, people forget about the increased effort for security of a native app.    I have a friend that built an app for a specific vertical and I tried to talk him into creating a web app first.  More than two years of development vs what would have been several months only to find the other issue I warned about.... users not willing to pay for apps on the Android platform.  A lot of wasted time and energy!