How has he never heard "I want to invent the future", I thought that was pretty much a staple. I've heard that in business consulting interviews for years.
Patents regard underlying functionality so if Preact infringes on the patent through using the same or sufficiently similar mechnism's to react functionality, it's a toss up but due to the nature of open source code the user might be liable.
Depends on the ruling of use of open source code that is in a way productized.
Also depends on if Preact's implementation is sufficient to infringe on React's patents (if they have any weight to them that is and are upheld)
Its not a random library, its extremely similar to React.
Ecosystem is so important these days, there might be technical reasons for choosing this but considering the support (knowing stack overflow answers will be available) and pre-existing component ecosystems for Vue & React, I can't see a reason anyone would pick this.
Disappointed to see no forward upfront stance on what Facebook will do if someone sues them for a patent infringement unrelated to React in any way.
Will note though that if Facebook does choose to revoke a license on the basis of getting sued for something unrelated it will definitely reflect poorly on FB in the developer community and reduce React's adoption.
Socket.io can't handle many connections you're right.
I would use (universal) Web Sockets (This is a good abstraction library, very easy to implement).