The UK waited until market forces made it more economically viable and our economy has certainly not suffered relative to the rest of Europe.
What about the rest of the world though? It's always going to be difficult assessing possible lost GDP, but being behind at the start can't have helped our cause.
The idea is that early state intervention builds a knowledge base, which you can then add to and eventually export. The military industrial complex is an example, and is one reason why Silicon Valley began in the first place. As some will know, ARPANET was a network developed for use in the American military, and was the forerunner of the internet. The World Wide Web was developed at CERN, state funded. Even before that, much work on digital communications and computing was undertaken by GCHQ and the then GPO, during and post-war. So very little private funding involved in these key technologies at all.
Ask yourself this- how many world class British software, networking, computing and technology companies can you name (and even less so that are British owned)? Obviously internet connectivity isn't in anyway solely responsible, but it's another technological and structural decision we got wrong, and I'm sure it's cost us.